Executive Summary

This article chronicles the transformation of gold and silver in the modern era through four interwoven narratives: (1) the dramatic evolution of monetary systems as political and economic decisions dismantled metallic monetary standards, (2) the explosive expansion of industrial and technological applications, (3) the scientific discoveries that revealed nanoscale properties and began a revolution, and (4) the market forces that drove both gold and silver to record prices – even as their purposes fundamentally changed.

Table Of Contents

1. Introduction

2. Brief History (1800 CE – Present Day)

3. Complete Chronology

4. Final Thoughts

5. Appendix

1. Introduction

The end of metallic monetary standards was not inevitable – it resulted from human decisions detached from the reality that Gold and Silver are sound money, and that fiat currencies represent control. But, the debate between Gold monometallism and Silver bimetallism, which seemed so consequential to contemporaries, proved irrelevant once both metals found more valuable applications outside of monetary systems.

The modern era of Gold and Silver, from 1800 to 2025, thus chronicles not the end of these metals’ importance, but rather their liberation from a single dominant idea.

Reader note – the parts of this series are:

• A History Of Gold And Silver In The Ancient Era – here.
• A History Of Gold And Silver In The Middle Ages – here.
• A History Of Gold And Silver In The Early-Modern Era – here.
• A History Of Gold And Silver In The Modern Era – here.
• A Complete History Of Gold And Silver – [coming soon]

2. Brief History (1800 CE – Present Day)

The Great Monetary Experiments

Britain’s 1816 establishment of the Gold Sovereign, weighing precisely 7.98 grams of 22-carat Gold and valued at exactly 20 shillings, marked more than a simple currency reform. It represented an ideological commitment to Gold as the ultimate arbiter of value, a decision that would reverberate through global finance for over a century. The 1819 Act for the Resumption of Cash Payments formalized this commitment, requiring the Bank of England to convert its banknotes into Gold coins on demand. 

Yet, even as Britain embraced its “Golden orthodoxy,” Silver quietly maintained its own monetary importance. The 19th century unfolded as a grand experiment in bimetallism versus monometallism, with the United States attempting to maintain both metals in circulation through fixed ratios. The 1834 Coinage Act’s establishment of a 16:1 Silver-to-Gold ratio overvalued Gold relative to Silver – presaging fundamental questions about whether two metals could simultaneously serve as money, or whether one must inevitably dominate.

The monetary tensions between Gold and Silver reached crisis points repeatedly. The 1873 Coinage Act, derisively called the “Crime of ’73” by Silver advocates, discontinued Silver dollar production and eliminated Silver’s unlimited coinage rights, effectively placing the United States on an unofficial Gold standard. This sparked decades of intense political conflict, culminating in William Jennings Bryan’s electrifying 1896 “Cross of Gold” speech advocating free Silver coinage at a 16:1 ratio. “You shall not crucify mankind upon a cross of Gold,” Bryan thundered, framing the debate as a moral crusade for debt-burdened farmers and workers against Eastern financial interests. He lost the election, and with it, Silver’s last realistic chance at monetary equality with Gold in the United States. 

The 1900 Gold Standard Act officially committed the United States to Gold at $20.67 per troy ounce, with all paper money backed by Gold reserves. 

War, Depression, and the End of the Classical Gold Standard

World War I shattered the classical Gold standard as nations suspended convertibility to print fiat money for war financing. Britain’s August 1914 Currency and Bank Notes Act effectively removed the country from Gold, authorizing unbacked paper notes. The United States imposed a Gold export embargo in 1917 under the Trading with the Enemy Act. The war demonstrated that Gold convertibility, once considered inviolable, could be suspended when national survival demanded it.

The interwar period saw failed attempts to resurrect the Gold standard. Winston Churchill’s 1925 decision to return Britain to Gold at its pre-war parity of $4.86 per pound resulted in an overvalued currency that caused deflation, unemployment, and economic distress—Britain was forced off Gold again in 1931 as the Great Depression deepened. Germany’s 1923 hyperinflation vividly illustrated the alternative to Gold backing: paper marks became worthless, used as wallpaper and fuel, while Gold and Silver prices skyrocketed as citizens desperately sought to preserve wealth in hard assets.

Franklin D. Roosevelt’s April 5, 1933 Executive Order 6102 marked a revolutionary moment: the United States government required citizens to surrender Gold coins, bullion, and certificates in exchange for paper dollars at $20.67 per ounce. Failure to comply carried severe penalties—up to $10,000 fines or 10 years imprisonment. The 1934 Gold Reserve Act then raised Gold’s official price to $35 per ounce, effectively devaluing the dollar by 41% against Gold. Gold was nationalized, privatized ownership criminalized, and the metal’s price fixed by government decree rather than market forces. Silver followed a parallel path of government intervention. The 1934 Silver Purchase Act authorized Treasury Silver purchases with the declared goal of increasing Silver in monetary stocks to 25% of combined Gold and Silver reserves. 

When China abandoned the Silver standard in 1935 after American Silver purchasing drove prices from $0.45 to $0.81 per ounce, causing deflation and capital flight, it marked another step in Silver’s monetary decline.

Bretton Woods and the Last Stand of Gold as Money

The 1944 Bretton Woods Agreement attempted to restore international monetary order by pegging currencies to the U.S. dollar, with the dollar alone convertible to Gold at $35 per ounce. This “Gold-exchange standard” placed the dollar—and by extension, American economic policy—at the center of global finance. The system created the International Monetary Fund and World Bank while establishing the framework that would govern international monetary relations for nearly three decades.

But, the Bretton Woods system’s inherent contradiction became increasingly apparent: as the global economy grew, demand for dollars (and thus U.S. payments deficits) increased, but this meant more dollars circulating relative to U.S. Gold reserves. French President Charles de Gaulle articulated this critique in his famous February 1965 speech, denouncing the dollar’s “exorbitant privilege” and advocating return to the Gold standard. France began aggressively exchanging dollars for Gold, secretly repatriating the metal over several years. France’s actions inspired other nations to convert dollars to Gold, putting immense pressure on the system.

The London Gold Pool, formed in November 1961 by eight central banks to maintain Gold’s $35 price, represented the system’s desperate effort at self-preservation. When France withdrew in 1967 and Gold market pressures intensified, the pool collapsed in March 1968. The London Gold Market temporarily closed on March 15, 1968, accompanied by a declared British bank holiday. The United States removed the “Gold cover” for bank deposits that same month, allowing monetary expansion while making more Gold available for international claims. The system was unraveling, sustained only by collective agreement to maintain the fiction of dollar-Gold convertibility.

Silver’s removal from U.S. coinage occurred gradually but inexorably. The 1964-1965 minting of final 90% Silver dimes, quarters, and half-dollars—totaling approximately 2.3 billion coins—preceded the Coinage Act of 1965, which changed these to copper-nickel clad compositions. By 1971, Silver’s elimination from American circulating coinage was complete. Canada followed suit in 1967-1968, reducing Silver content from 80% to 50% before switching circulation coins entirely to nickel by August 1968.

The Nixon Shock and the Birth of Fiat Currency

President Richard Nixon’s August 15, 1971 announcement suspending dollar convertibility to Gold—the “Nixon Shock”—severed the last connection between precious metals and the international monetary system. This wasn’t presented as a permanent policy, but as a temporary measure to address speculation against the dollar. Yet, temporary became permanent: by March 1973, when the Bretton Woods system of fixed exchange rates effectively ended and major currencies floated freely, the age of metallic money standards was over. For the first time in history, the global monetary system rested entirely on government fiat—paper money backed not by precious metals, but by governmental authority and economic productivity.

President Gerald Ford’s December 31, 1974 signing of Executive Order 11825 ended the 41-year ban on private Gold ownership, allowing Americans to legally own, buy, and sell Gold again. This marked Gold’s transformation from government-controlled monetary reserve to private investment asset and store-of-value collectible. 

The transition unleashed Gold and Silver prices from government controls. Gold climbed from $35 per ounce in 1971 toward $226 by 1978, then surged to over $850 by early 1980, driven by soaring inflation, the 1978 Iranian Revolution disrupting oil supplies, and 1979 Soviet invasion of Afghanistan creating geopolitical tensions. Silver experienced even more dramatic volatility: the Hunt brothers’ 1973-1980 attempt to corner the market through futures contracts and physical purchases amassed over 200 million ounces and drove prices toward $50 per ounce before “Silver Thursday” in 1980 saw prices crash to around $10 as exchanges restricted buying and raised margin requirements. The Hunt brothers were financially ruined, and many brokerage firms with them—a spectacular demonstration of how free markets could both enable and punish speculative excess.

The Nanotechnology Revolution

While Gold and Silver’s monetary roles were ending, their scientific and technological importance was exploding through understanding of their nanoscale properties. 

The 1971 work by W.P. Faulk and G.M. Taylor pioneering immunoGold labeling for electron microscopy, followed by 1973 refinements to the Turkevich method for controlled Gold nanoparticle synthesis, established these metals as critical tools for biological research. The 1973-1974 discovery of Surface-Enhanced Raman Scattering (SERS) by Fleischmann and colleagues revealed that molecules on roughened Silver electrodes produced unexpectedly intense Raman spectra—a phenomenon that would enable single-molecule detection by 1997.

Then came rapid advances in synthesizing and characterizing metal nanoparticles with precise control over size and shape: For example, the 1994 Brust-Schiffrin method for producing highly stable thiol-derivatized Gold nanoparticles became a standard technique. And, Charles R. Martin’s 1994 development of template synthesis using track-etched membranes enabled production of uniform Silver nanowires with diameters as small as 10 nanometers. The ability to engineer metallic structures at the nanoscale with specific optical, electrical, and catalytic properties opened entirely new technological possibilities. Meanwhile, Robert Burrell’s 1995 invention of nanocrystalline Silver technology for Acticoat wound dressings created the world’s first commercial therapeutic application of nanotechnology, effective against over 150 microorganisms including antibiotic-resistant strains like MRSA. And, DNA-directed assembly of Gold nanoparticles into ordered structures, demonstrated by Mirkin and Paul Alivisatos in 1996, opened possibilities for programmable nanoscale architectures. 

The 2000 development of scanometric DNA array detection using Gold nanoparticle probes by Chad Mirkin and colleagues led to commercial diagnostic systems. Younan Xia’s 2002 work at the University of Washington formalizing the polyol synthesis method—reducing Silver in hot ethylene glycol with polyvinylpyrrolidone as a capping agent—achieved 90% yields and became an industry standard. By 2009, researchers demonstrated Silver nanowire networks as flexible transparent conducting films with the highest conductivity ratios ever observed for nanostructured films, enabling applications in touchscreens and flexible electronics. Finally, The 2012 demonstration of thousand-fold enhancement of single-molecule fluorescence using Gold nanorods, and subsequent work on Gold nanoparticle-mediated cancer therapy through photothermal treatment and radiotherapy, positioned these materials as potential tools for both diagnosis and treatment of disease. 

By 2024, the majority of global public health problems were treated with green synthesized Silver nanoparticles (AgNPs), and, already this year, 2025 papers have reported record 53.59% photoluminescence quantum yield for Silver selenide quantum dots at 1140 nanometers (enabling near-infrared biological imaging), heavy-metal-free Silver selenide quantum dot photodetectors rivaling toxic alternatives, and novel synthesis methods achieving unprecedented control over Silver nanostructure morphology.

The Present and Future

The years 2024-2025 witnessed unprecedented price appreciation reflecting multiple converging factors. Gold shattered records, reaching above $4,300 per ounce by early December 2025, driven by geopolitical instability, high U.S. government debt, a weakening dollar, and continued central bank buying. Silver reached its own records around $59 per troy ounce in December 2025, with over 100% annual gains driven by safe-haven demand, industrial use in green technology (EVs, solar panels), and persistent supply deficits.

The modern history of Gold and Silver thus represents not decline from monetary glory, but transformation into forms their 19th-century champions could never have anticipated. 

Gold transitioned from monetary standard to ultimate safe-haven asset and store of value, its price freed from government controls to reflect market perceptions of economic stability and government policy credibility. Silver transformed from monetary metal to essential industrial material, its unique electrical conductivity, optical properties, and antimicrobial effects making it irreplaceable in technologies from smartphones to solar panels to medical devices. 

Both metals found entirely new identities at the nanoscale, where their size-dependent optical, electrical, and catalytic properties enable applications from cancer therapy to quantum computing.

3. Complete Chronology

From Britain’s 1816 Gold Sovereign to 2025’s record price levels, from daguerreotypes to quantum dots, from Gold rushes to green synthesis—this 209-year chronology encompasses not merely price fluctuations and policy changes, but the fundamental reconceptualization of the purpose of these metals:

1816 – The Guinea was officially replaced by the Gold Sovereign (weighing 7.98 grams of 22-carat Gold and valued at exactly 20 Shillings) in 1816 as part of the second Great Recoinage Act; French dentist Auguste Taveau develops the modern dental amalgam, mixing melted Silver coins and mercury. He began using it as a dental restorative material in 1826

1819 – The Act for the Resumption of Cash Payments set the date (originally 1823, but implemented earlier in 1821) by which the Bank of England had to resume converting its banknotes into Gold coins on demand at a fixed price. The 1819 Act was a key step in Britain’s adoption of the Gold standard by mandating the resumption of convertibility of banknotes to Gold

1823 – First official reports of Gold findings in Australia. J. McBrien found Gold particles in the sand near the Fish River while surveying the area between Rydal and Bathurst. He recorded the discovery in his fieldbook on February 15, 1823. The colonial government kept the discovery secret. They feared that widespread knowledge of Gold would cause people to stop working, potentially destabilizing society and the economy, which was still heavily reliant on convict labor and public service. This is considered the first authentic reference to a Gold discovery in Australia, although public Gold rushes would not begin until later, most famously with the discoveries in the 1850s

1830 – Louis Daguerre and Nicéphore Niépce develop the daguerreotype in the 1830s, which used Silver-halide (specifically Silver iodide) on a Silver-coated copper plate

1831 – British chemist Michael Faraday begins experiments demonstrating electromagnetic induction and works with various metals, including copper and Silver, in electrical experiments, establishing foundations for understanding electrical properties of conductors

1834 – The United States Coinage Act reduced the Gold content of the U.S. Eagle from 247.5 grains to 232 grains of pure Gold – consistent with the 16∶1 Silver-to-Gold ratio the act established. The Coinage Act of 1834 overvalued Gold relative to Silver, which initiated the flow of Silver out of circulation

1837 – The Mint Act set the fineness of U.S. Gold and Silver coins to a consistent 0.900 (90% pure metal)

1840 – Birmingham inventor George Richards Elkington patents electroplating process (British Patent 8447) using cyanide bath solutions to deposit Silver onto base metals, revolutionizing commercial manufacturing of plated Silverware

1844 – The Bank Charter Act institutionalized the Gold standard in Britain by dividing the Bank of England into an Issue Department and a Banking Department and imposing strict limits on the amount of unbacked banknotes the Issue Department could circulate (the fiduciary issue). Any notes issued beyond this limit had to be fully backed by Gold or Silver bullion, effectively creating a direct, legislated link and ratio between Gold reserves and the overall money supply

1848 – James Marshall discovers Gold nuggets at Sutter’s Mill near Sacramento, California, on January 24, triggering the California Gold Rush that transforms San Francisco from a town of 1,000 to 25,000 people by the early 1850s

1851 – Edward Hargraves is credited with the 1851 discovery of Gold near Orange in New South Wales (at Lewis Ponds Creek near what Hargraves named Ophir, after the biblical city of Gold) – which triggered the Australian Gold rushes. However, it was later acknowledged that his partners, John Lister and the Tom brothers, were the ones who actually found payable Gold in the area – the large nuggets that made the discovery newsworthy. Hargraves claimed the discovery as his own to secure a government reward, a fact that was only officially recognized decades later after an official 1890 investigation. Gold is discovered at Ballarat and Bendigo Creek in Victoria, Australia, within six months of the New South Wales discovery

1852 – Gold deposits are discovered in Tasmania. The first payable alluvial Gold deposits were found by James Grant at Mangana and Tower Hill Creek, sparking the Tasmanian Gold rushes

1853 – The United States Coinage Act of February 21 reduces Silver content in subsidiary coins (Half Dimes, Dimes, Quarters, and Half Dollars) by approximately 7% to address hoarding and melting, while the Silver Dollar remains unchanged

1856-1857 – Michael Faraday conducted year-long research on colloidal Gold, discovering the first metallic colloids by reducing aqueous Gold chloride with phosphorus in the presence of carbon disulfide, producing a “beautiful ruby fluid”; published “Experimental Relations of Gold (and Other Metals) to Light” in Philosophical Transactions of the Royal Society of London (1857, Vol. 147, pp. 145-181), establishing the scientific foundation for Gold nanoparticle research

1857 – The SS Central America, dubbed the “Ship of Gold,” sinks in a hurricane off the Carolina coast on September 12 carrying an estimated 30,000 pounds (13,600 kg) of California Gold Rush treasure, contributing to the Panic of 1857; 425 of the 578 passengers and crew perish in what becomes America’s greatest peacetime maritime disaster

1858 – Gold discovered in British Columbia, attracting 25,000 prospectors; The “Welcome Nugget,” weighing 69 kg (2,217 troy ounces), is discovered at Ballarat, Victoria, Australia

1859 – The Comstock Lode discovery in Nevada in June reveals ore deposits containing Silver and Gold, marking the first major Silver discovery in United States history

Early 1860s – The Washoe Silver milling process, developed at Nevada mines, increases Silver extraction efficiency through steam-heated iron pans that reduce processing time from weeks to hours, replacing earlier amalgamation methods for Comstock ore processing

1861 – Thomas Graham coins term “colloid” and studies the dialysis of Silver nanoparticle solutions

1862 – The United States declares paper money as legal tender for the first time during the Civil War, marking the first use of fiat currency in the U.S. This new paper currency was soon nicknamed “greenbacks” because of the green ink used on the back of the notes

1865 – The Latin Monetary Union treaty signed between France, Belgium, Italy, and Switzerland standardizes Silver coinage to facilitate trade between member nations. The treaty set the standard for the 5-Franc coins at 25 grams of fine Silver, at 90% Silver purity, and for other Silver coins, such as the 2 francs, 1 franc, 50 centimes, and 20 centimes, at 83.5% Silver purity

1867 – Canada introduces its own Gold dollar at par with the U.S. dollar and with a fixed exchange rate to the Gold Sovereign; The discovery of a large Goldfield by James Nash in Gympie, in 1867, triggered the Gympie Gold rush – which is considered the first major Gold rush in Queensland. This event provided a much-needed economic boost to the young colony, with 25,000 people flocking to the area within months to seek their fortunes

1869 – The “Welcome Stranger,” the largest alluvial Gold nugget ever found, is discovered by John Deason and Richard Oates near Moliagul, Victoria, Australia. Weighing 72.02 kg (2,284 troy ounces) of pure Gold after smelting, the nugget was so large that it had to be broken on a blacksmith’s anvil to fit on the bank scales

1870 – The Crown Point-Belcher bonanza discovered on the Comstock Lode extends from the 900 to 1,500-foot level, yielding ore with precious metal value of 54 percent Gold and 46 percent Silver over four years of production

1871 – Germany adopts the Gold Mark following unification, with legislation passed on December 4 beginning the process of demonetizing Silver-based currencies and selling government Silver reserves as the German Empire transitions to the Gold standard

1871-1872 – Gold is discovered in the Northern Territory of Australia. Traces of Gold were found by workers digging post holes for the Australian Overland Telegraph line near Pine Creek, south of Darwin, in late 1871. This discovery led to the first Northern Territory Gold rush, with prospectors arriving in Port Darwin the following year. The first significant discovery in the region occurred in 1872 at Yam Creek

1872 – The Holtermann Specimen, the largest Gold specimen ever discovered (not largest nugget ever discovered – that was the “Welcome Stranger” of 1869), is found by Bernhardt Otto Holtermann at Hill End, New South Wales, Australia, weighing 290 kg total with 93 kg (2,990 troy ounces) of Gold content embedded in a mass of quartz and slate

1873 – Germany advances Silver demonetization by formally adopting the Gold Mark as currency on July 9, 1873, following the 1871 cessation of Silver Taler coinage; The United States Coinage Act of 1873, called the “Crime of ’73” by critics, discontinues Silver Dollar production, eliminating Silver’s unlimited coinage rights and sparking decades of monetary reform movements as the U.S. is placed on an unofficial Gold standard

1875 – The U.S. Specie Resumption Act sets 1879 as the date for resuming Gold convertibility

1879 – The Alaskan territory organizes its first mining district. This event was a key milestone in the development of mining in the region and preceded major Gold strikes, such as the one in the Silver Bow Basin near present-day Juneau the following year

1880 – Carl Credé implements 2% Silver nitrate eye drop prophylaxis for newborns at his Leipzig hospital on June 1, 1880, reducing neonatal conjunctivitis incidence from 10% to 0.3% and preventing widespread infant blindness from bacterial infections

1883 – Boundary rider Charles Rasp discovers the Broken Hill lead-Silver-zinc deposit in Australia on September 5, 1883, which becomes one of the world’s largest Silver-lead-zinc ore bodies, producing continuously for over 140 years

1886 – Gold is discovered on the Witwatersrand in South Africa, leading to the founding of Johannesburg and massive Gold production. The Witwatersrand became the richest Goldfield in history, producing an estimated 40–50% of all the Gold ever mined worldwide

1888 – George Eastman’s Kodak camera popularizes Silver halide film photography, creating new Silver demand as amateur photography enters consumer markets through roll film technology

1889 – M. Carey Lea pioneers the synthesis of stable Silver colloids (nanoparticles), observing various colors and noting their dependence on the particle characteristics. His work is considered pioneering in the field, and later scientific advancements, particularly by Richard Zsigmondy in 1925 (who won the Nobel Prize for his work on colloids), confirmed that Lea’s “allotropic” Silver was actually a colloid composed of ordinary Silver nanoparticles

1890 – The Sherman Silver Purchase Act requires United States Treasury monthly purchases of 4.5 million ounces of Silver, doubling previous Bland-Allison requirements and supporting Western mining interests

1891 – Carl Siegmund Franz Credé first uses a form of colloidal Silver for wound sterilization

1892-1893 – The Gold rush at Coolgardie in Western Australia begins in September 1892, when Arthur Bayley and William Ford find Gold. The Gold rush at Kalgoorlie followed shortly after, beginning in June 1893, when prospectors Patrick “Paddy” Hannan, Tom Flanagan, and Dan Shea find a rich Gold reef at Mount Charlotte

1893 – In June 1893, acting on the recommendations of the Herschell Committee, the British Indian government closed its mints to the free coinage of Silver. This broke the link between the rupee and the value of Silver, with the intention of eventually introducing a Gold standard. India was a major importer of Silver, accounting for about a quarter of the annual global production. Its abandonment of the Silver standard removed a significant pillar of support for the global Silver price. This move, along with the subsequent repeal of the Sherman Silver Purchase Act in the United States in November 1893 – partially in response to the panic and Silver’s decline, ending mandatory government Silver buying – caused Silver prices to depreciate sharply and destabilized global Silver markets – deepening American economic depression

1894-1897 – Collargol, made of 10-nm Silver nanoparticles, was developed between 1894 and 1897 by Crede. It was initially used to treat various infections, particularly gonorrhea, as a less irritating alternative to Silver nitrate

1896 – William Jennings Bryan delivers his “Cross of Gold” speech at the Democratic National Convention on July 9, advocating 16:1 Silver-Gold ratio and free Silver coinage during his presidential campaign

1896-1897 – Gold is discovered in the Klondike region of the Yukon on August 16 by a group of local miners, including George Carmack, Skookum Jim, and Dawson Charlie. Their find on Rabbit Creek, later renamed Bonanza Creek, sparked the famous Klondike Gold Rush – with news reaching the outside world in 1897 and attracting an estimated 100,000 prospectors

1898 – Richard Adolf Zsigmondy prepared the first dilute colloidal Gold solutions in 1898. His work demonstrated that colloidal solutions are heterogeneous, with particles too small to be seen with a regular microscope, and this research earned him the Nobel Prize in Chemistry in 1925; Georg Bredig developed the electric dispersion method, also called Bredig’s Arc method, which is an electric arc method used to create colloidal solutions of metals like Silver. The process involves using an electric arc between two metal electrodes to vaporize the metal, which then condenses in a cold, stabilized dispersion medium to form nanoparticles

1898-1899 – Major Gold strikes occurred at Nome, Alaska, starting in September 1898, with the discovery on Anvil Creek by Jafet Lindeberg, Erik Lindblom, and John Brynteson, collectively later known as the “Three Lucky Swedes”. That same year, Gold was discovered in the beach sands for miles along the coast. News of the discoveries spread over the winter, and, by 1899, thousands of prospectors had arrived. The influx of people made Nome Alaska’s largest city for a time, with a population reaching 10,000 by 1899 and growing even more in the following years

1900 – The 1900 Gold Standard Act officially put the United States on the Gold standard, setting the price of Gold at $20.67 per troy ounce, and established that all paper money be backed by Gold reserves. President William McKinley signed the act into law on March 14, 1900

1901 – Albert Barnes and Hermann Hille made Argyrol commercially available (trademarked in 1902). The compound, a mild Silver protein antiseptic, became a standard treatment for preventing gonorrheal infections and associated infant blindness in maternity wards worldwide, making Barnes a fortune before the advent of antibiotics

1902 – Italian immigrant Felix Pedro discovered Gold near the area that would become Fairbanks, Alaska, marking the beginning of the Fairbanks Gold Rush. Pedro found Gold 14 feet deep on bedrock at an unnamed creek, later named Pedro Creek, located 12 miles northeast of E.T. Barnette‘s trading post. He reportedly exclaimed, “There’s Gold in them there hills!”. Barnette sent a man to Dawson City to spread the news, which brought a stampede of prospectors to the area and transformed the small settlement into a major town, ultimately leading to the city’s nickname, “The Golden Heart City”

1903 – Richard Zsigmondy and Henry Siedentopf invented the ultramicroscope, which uses dark-field illumination to make sub-microscopic particles, such as Silver nanoparticles, visible by observing their scattered light. This method makes particles visible as bright specks against a dark background, even if they are smaller than the wavelength of light

1908 – Gustav Mie publishes “Beiträge zur Optik trüber Medien” providing exact mathematical solutions for electromagnetic wave scattering by spherical Gold and Silver nanoparticles, explaining size-dependent optical properties

1909 – Zsigmondy published “Colloids and the Ultramicroscope“, a manual of colloid chemistry and ultramicroscopy, that, in essence, is a manual for the study of what we now refer to as nanoparticles. Using the ultramicroscope, Zsigmondy was able to estimate the size of Gold particles, some as small as one ten-millionth of a millimeter (i.e., less than 10 nm). This made him one of the first to measure and classify materials in the nanometer range, introducing the nanometer explicitly as a unit for particle size. He also developed methods to synthesize Gold colloids of specific, controllable sizes, including a two-step “nuclear” or “seed-mediated” method that is a precursor to some modern nanoparticle synthesis techniques. Zsigmondy’s work laid the groundwork for understanding the unique size-dependent properties of metallic nanoparticles that are now central to modern Gold and Silver nanotechnology research and applications

1909-1911 – The Porcupine Gold Rush occurred in the region around Timmins, Ontario, starting in 1909 and developing fully by 1911. Significant Gold discoveries, including the Dome, Hollinger, and McIntyre deposits, were made during this time, leading to a massive influx of prospectors and the founding of the community that would become Timmins. These discoveries made the Porcupine area the largest Gold-producing region in North America for many years and led to the rapid growth of the towns of South Porcupine, Schumacher, and Timmins

1911 – The 1911 edition of the British Pharmaceutical Codex includes information on colloidal Silver preparations, and, by the 1920s, the Codex listed colloidal Silver as a standard antimicrobial treatment

1912 – The Stockholm Summer Olympics award the last Olympic Gold medals made of solid Gold – all subsequent Olympic Gold medals are required to be at least 92.5% Silver with a minimum 6-gram Gold plating

1913 – Theodor Svedberg utilized an ultracentrifuge to analyze the size distributions of Silver nanoparticles (as well as Gold, barium sulfate, clay, and arsenic trisulfide sols). His work confirmed the existence of particles within the range of 5-100 nanometers and established fundamental characterization techniques for colloidal systems using analytical ultracentrifugation (AUC). For this pioneering work on disperse systems, Svedberg was awarded the Nobel Prize in 1926; The original Federal Reserve Act of 1913 required each Federal Reserve Bank to maintain a minimum Gold reserve of 40% against the Federal Reserve Notes it issued into circulation. Additionally, the Act required a 35% Gold reserve against member bank deposits at the Fed. These requirements remained in effect until they were lowered in 1945 and eventually eliminated entirely in 1968, severing the final legal link between the U.S. dollar and Gold

1914 – World War I begins. Many countries, including Britain, suspend Gold convertibility to finance war efforts, allowing them to print fiat money. The Currency and Bank Notes Act was passed in the UK in August 1914, which effectively took Britain off the Gold standard and authorized the issuance of paper banknotes not backed by Gold

1917 – The United States imposed an embargo on Gold exports under the Trading with the Enemy Act of 1917, which required special permission from the Secretary of the Treasury to export Gold. This effectively functioned as a partial suspension of Gold payments to other countries

1918 – George Eastman introduced the first flexible medical X-ray film, employing Silver halide emulsions, which began to replace glass plate X-rays by the 1920s

1918-1921 – The Pittman Act passed in 1918 authorized the melting of up to 350 million Silver dollars to support Britain during WWI. Approximately 270 million dollars in Silver were melted, sold to Britain for $1.00 per ounce to help manage currency needs in India, and the proceeds were used to purchase and later replace the Silver at the same price beginning in 1921

1919 – The United States ended a wartime embargo on Gold exports in June 1919, which had functioned as a temporary suspension of the Gold standard during World War I. This action was part of the international effort to return to a Gold standard, which ultimately failed in the face of the Great Depression

1920 – The Gold and Silver (Export Control) Act 1920 was passed in the UK and enacted to continue wartime controls on the export of Gold and Silver, requiring a license for such transactions. It was a continuation of existing powers, as the temporary wartime legislation was set to expire

1923 – During Germany’s  Weimar Republic 1923 hyperinflation crisis, the paper Mark became essentially worthless, and citizens sought to preserve their wealth by acquiring hard assets like Gold and Silver, as prices for these metals skyrocketed. The hyperinflation was so severe that paper money was used for everyday purposes, such as wallpaper and fuel, while the value of Gold and Silver rose astronomically

1925 – Chancellor of the Exchequer, Winston Churchill, announced Britain’s return to the Gold standard, re-establishing the value of the pound sterling at its pre-World War I parity of $4.86 per pound. The decision was intended to stabilize the economy, but the resulting overvalued pound led to deflation, high unemployment, and other economic problems, and Britain was forced off the Gold standard again in 1931

1931 – Britain abandons the Gold standard as the Great Depression deepens; Catalyst technology for converting ethylene to ethylene oxide developed by French chemist Theodore Lefort for the chemical industry, enabling efficient plastics manufacturing at elevated temperatures. Ethylene oxide is also a critical intermediate chemical used to make numerous consumer products, including detergents, antifreeze, and polyester fibers. Until 1931, the only method was an inefficient chlorohydrin process – Lefort’s discovery, which enabled a direct catalytic oxidation process using air and a Silver catalyst, became vital for the chemical industry

1933 – On April 5, 1933, President Franklin D. Roosevelt issued Executive Order 6102, which required U.S. citizens to surrender their Gold coins, bullion, and certificates to the Federal Reserve in exchange for paper dollars at a fixed price of $20.67 per ounce. This order was part of the government’s effort to stimulate the economy during the Great Depression by taking Gold out of private hands and giving the government more control over the money supply. Failure to comply with the order carried a significant penalty, including a fine of up to $10,000 or a prison sentence of up to 10 years

1934 – Langmuir and Blodgett create organized Silver nanoparticle monolayers, pioneering self-assembly techniques. This work, and the Langmuir-Blodgett technique itself, is widely regarded as an early example of molecular engineering and controlled assembly at the nanoscale; The Silver Purchase Act of 1934 authorizes Treasury Silver purchases. The declared policy was to increase the proportion of Silver in the monetary stocks until it reached one-fourth (25%) of the total monetary value of Gold and Silver reserves – often stated as a one-to-three ratio of Silver to Gold. Price Limit: The Treasury was directed not to pay a price in excess of the monetary value of the Silver (which was around $1.29 per ounce at the time). For Silver already situated within the U.S. as of May 1, 1934, the price limit was capped at 50 cents per ounce; The Gold Reserve Act is passed, nationalizing all Gold and Gold certificates, requiring their surrender to the U.S. Treasury. This applied to the Federal Reserve and private individuals/institutions (following the precursor Executive Order 6102 in 1933). The official statutory price of Gold was raised from the previous rate of $20.67 per ounce to $35 per ounce. This increase in the price of Gold effectively devalued the dollar by approximately 41% against Gold. The main goal of this action was to expand the money supply, stimulate the economy during the Great Depression, and give the government greater control over monetary policy

1935 – China abandons the Silver standard in November after the United States Silver Purchase Act drives prices from $0.45 to $0.81 per ounce, causing deflation and capital flight as Silver flows abroad

1936-1937 – Construction of the United States Bullion Depository at Fort Knox is completed in December at a cost of $560,000. The first Gold shipments arrived between January and July 1937 – from the Philadelphia Mint and New York Assay Office, totaling 157,820,192 troy ounces

1937 – The use of supported Silver catalysts for ethylene epoxidation, initially developed by French chemist Theodore Lefort in 1931, was first industrialized by Union Carbide; Also in 1937, American inventor Stanley Donald Stookey discovered photosensitive glass – containing Silver nanoparticles – while at Corning Glass Works. His discovery paved the way for other inventions, such as photochromic glass for eyeglasses and the durable glass-ceramic material that became known as CorningWare, and also contributed to the development of eyeglasses, sunglasses, cookware, defense systems, and electronics. Stookey received a patent for this discovery in 1950

1939-1945 – Silver was incorporated into the high-power cavity magnetron tubes, which were the key technological breakthrough enabling effective microwave radar. The British-invented magnetron design was shared with the US via the Tizard Mission in 1940, leading to mass production by companies like Raytheon. American engineers developed efficient ways to manufacture the complex, finely detailed, magnetron anode blocks by Silver soldering stacked metal sheets together. Allied forces produced thousands of these radar units through 1945, incorporating Silver components for detection systems in aircraft, ships, and ground stations. The industrial demand for Silver during World War II was so high that the U.S. government borrowed thousands of tons of Silver from Treasury reserves for various military applications, such as in Silver-zinc batteries for torpedoes and for the Manhattan Project – which borrowed 14,700 tons of Silver from the U.S. Treasury in 1942, using it as a substitute for the scarce copper needed for electromagnets in the calutrons at Oak Ridge. After the war, most of the Silver was returned to the Treasury, but a small amount, 67 tons, was kept for a while for use in separating isotopes for medical research before it was also returned in 1970

1941 – Boris Derjaguin and Lev Landau introduced the theory that would become part of the DLVO framework, explaining colloidal stability through the balance of van der Waals attraction and electrostatic repulsion forces. The DLVO Theory, developed independently by Boris Derjaguin and Lev Landau in 1941 (published in Russia and the Acta Physicochimica URSS), and by Evert Verwey and Theodor Overbeek in 1948 (published in Theory of the Stability of Lyophobic Colloids), provides the fundamental framework for understanding the stability and aggregation behavior of various colloidal dispersions – including modern applications to Silver nanoparticles

1943 – President Franklin D. Roosevelt becomes the only person other than authorized personnel to access Fort Knox vaults. The Fort Knox vaults have only been opened to non-authorized visitors on three officially reported occasions in their history: 1943, 1974, and 2017

1944 – The Bretton Woods Agreement establishes a new international monetary system with currencies pegged to the U.S. dollar, which is convertible to Gold at $35 per ounce. The system was designed to promote global economic stability and prevent the competitive currency devaluations that had occurred in the interwar period. It also led to the creation of the International Monetary Fund (IMF) and the World Bank – both also in 1944. The original IMF Articles of Agreement required member countries to pay their subscription quotas in Gold – as the smaller of either 25% of the subscription total, or 10% of their net official Gold and dollar holdings – so that the IMF could build its Gold reserves to support member countries in need. The system lasted until 1971 when President Richard Nixon ended the dollar’s convertibility to Gold, leading to the current era of mostly floating exchange rates

1946 – Kodak resumes civilian photographic film production following wartime restrictions, contributing to post-war growth in Silver consumption for photography. This event marked a “transition period” (1946-1971) for Silver, during which post-war economic growth fueled the demand for photographic film and industrial applications

1946-1947 – The cloud seeding proof of concept was first discovered by Vincent J Schaefer, Bernard Vonnegut, and Irving Langmuir in 1946. Schaefer and Langmuir were researching icing on aircraft at the General Electric Company’s research laboratory after World War 2. By investigating the production of particles of various sizes, and their behavior in the atmosphere, they discovered that tiny particles could be used to produce ice. They were able to nucleate ice by introducing small particles in a laboratory-made cloud in a freezer, with dry ice to create snow. Shortly after, Bernard Vonnegut realized that Silver iodide particles were even more effective than dry ice at creating ice formations. This was because AgI’s molecular structure is nearly identical to that of ice, making it an ideal nucleus for water vapor to freeze onto. This discovery marked a major advancement in weather technology and led to the creation of the Project Cirrus cloud seeding project in 1947

1950 – The LaMer model was introduced by Victor LaMer to explain how monodisperse particles are formed through a process of “burst” or “instantaneous” nucleation followed by diffusion-controlled growth. It is a model of colloidal particle formation used to explain how nanoparticles with similar sizes are created – including Silver and Gold nanoparticles

1951 – J. Turkevich, P.C. Stevenson, and J. Hillier published Nucleation and growth process in the synthesis of colloidal Gold (Discussions of the Faraday Society, Vol. 11, pp. 55-75), describing citrate reduction of chloroauric acid (HAuCl₄) to produce monodisperse spherical Gold nanoparticles (approximately 10-20 nm diameter), establishing what became known as the Turkevich method

1954 – The U.S. Treasury amends Gold Regulations to expand the definition of collectible coins exempt from confiscation. The original Executive Order 6102 of 1933 had required citizens to surrender most of their Gold, with an exception for “Gold coins having a recognized special value to collectors of rare and unusual coins”. The 1954 amendment clarified and expanded this exemption to specifically include all Gold coins made prior to April 5, 1933, codifying this into 31 CFR Section 54.20. This action provided a clear legal basis for the continued private ownership of pre-1933 U.S. Gold coins – and helped lay the foundation for the modern numismatic market for these items

1957 – Rufus Ritchie predicts surface plasmons in thin Silver films, laying the theoretical foundation for understanding the optical properties of Silver nanoparticle 

1958 – European currencies become convertible, making the Bretton Woods system fully operational. This marked the end of the transitional period that began with the Bretton Woods Agreement in 1944, as a system of fixed exchange rates tied to the U.S. dollar, which was in turn convertible to Gold, was finally established globally

1960-1961 – A run in the London Gold market sent the price of Gold to $40 an ounce on October 20, 1960. In response, the London Gold Pool was formed on November 1, 1961. The pool consisted of a group of eight central banks (Great Britain, West Germany, Switzerland, the Netherlands, Belgium, Italy, France, and the United States). In order to keep the price of Gold at $35 an ounce, the group agreed to pool Gold reserves to intervene in the London Gold market in order to maintain the Bretton Woods system – with the U.S. contributing 50% of the 240-tonne pool. The pool collapsed in March 1968

1962 – Ryogo Kubo developed a theory predicting that the continuous electronic energy band structures found in bulk metals would become discrete in very small metallic nanoparticles – including Silver and Gold nanoparticles – due to the quantum size effect (QSE). He proposed that the mean energy level spacing (𝛿𝐾𝑢𝑏𝑜) would be inversely proportional to the number of atoms in the particle and the bulk density of states at the Fermi energy

1964-1965 – The United States mints final 90% Silver Dimes, Quarters, and Half-Dollars, totaling approximately 2.3 billion coins. The Coinage Act of 1965 officially changed the composition of these coins to a copper–nickel clad sandwich. This transition was driven by a Silver shortage, caused by factors like increased coin-collecting and the proliferation of vending and coin-operated machines that sequestered coins

1965 – NASA developed Silver ion water purification systems for the Apollo program to disinfect water without using harsh chemicals like chlorine. After its success in the Apollo program, NASA licensed the technology for commercial use. A modified version of the “Electrolytic Silver Ion Cell” is now used in various applications, including swimming pools, hot tubs, fountains, and cooling towers; In a February 1965 speech, French President Charles de Gaulle criticized the dollar’s international status and advocated for a return to the Gold standard in his “Criterion Speech”, arguing that the U.S. dollar’s global dominance, known as “the exorbitant privilege,” was unstable and a result of the U.S. balance of payments deficit. With the U.S. able to print money to finance its deficits without penalty, France began aggressively exchanging its dollar holdings for Gold, a policy known as “Vide-Gousset”. The Gold was secretly repatriated to France over several years to avoid detection. France’s actions, combined with its public criticism, spurred other nations to convert their dollars to Gold as well, which put immense pressure on the Gold Pool and the Bretton Woods system. This trend of converting dollars to Gold was a significant factor leading to the collapse of the Bretton Woods system and Nixon’s decision to end the dollar’s Gold convertibility in 1971

1967 – France announces withdrawal from the London Gold Pool. This withdrawal was a significant event that contributed to the eventual collapse of the entire Gold Pool system in March 1968; On 18 November 1967, Britain devalued the pound sterling from $2.80 to $2.40 per pound in an event known as the “Sterling Crisis”. This 14.3% devaluation was a response to economic difficulties, declining competitiveness, and pressure on the balance of payments. 

1967-1968 – The Silver content in Canadian dimes and quarters was reduced from 80% to 50% in the summer of 1967. By August 1968, the Royal Canadian Mint permanently switched all circulation coins (dimes, quarters, half-dollars, and dollars) to a nickel composition, due to the cost of Silver making them worth more than their face value

1968 – The United States Treasury stops redeeming Silver certificates after the public claims 116 million ounces during six months of redemption operations ending June 24. This action effectively ended the link between Silver and U.S. paper currency, including the one-dollar bill, which was then replaced by the Federal Reserve note as the standard currency – backed by financial assets rather than a physical commodity like Silver. And, in March 1968, the U.S. Congress removed the “Gold cover” for bank deposits, allowing for the expansion of the money supply and making more Gold available to meet international claims. It’s important to note that this repeal did not immediately end the Gold standard. The requirement for a 25% Gold reserve on the currency itself (Federal Reserve notes) remained in effect until 1971 and the “Nixon Shock”; Also in 1968, the London Gold Market was temporarily closed on March 15th at the request of the United States government due to the collapse of the London Gold Pool. This closure was accompanied by a declared bank holiday in the United Kingdom

1969 – The Apollo 11 lunar module, the “Eagle,” used Silver-zinc batteries to power its mission on the Moon. Silver-zinc was chosen for its high energy density, meaning it could store a large amount of energy in a relatively small and light package, which was crucial for the mission. These batteries, which powered all critical functions for the landing and surface stay – from the life support systems to the ascent engine that lifted the astronauts back to orbit – were not rechargeable, so engineers meticulously calculated power usage to ensure there was enough power to complete the mission, including a reserve for emergencies

1971 – The United States changed the 40% Silver content of Kennedy Half-Dollars to a copper-nickel clad metal, completing Silver’s elimination from American circulating coinage. That same year President Richard Nixon announced the suspension of dollar convertibility to Gold in the “Nixon Shock” – effectively ending the Bretton Woods system and fully detaching the dollar from Gold. This severed the last connection between precious metals and international monetary systems, beginning the age of fiat currency worldwide; Also in 1971, W.P. Faulk and G.M. Taylor published “An immunocolloid method for the electron microscope” (Immunochemistry, Vol. 8, pp. 1081-1083), pioneering the use of antibody-conjugated Gold nanoparticles for electron microscopy visualization of Salmonella antigens, launching the field of immunoGold labeling

1973 – The Bretton Woods system of fixed exchange rates effectively ended in March 1973 when major currencies, led by the U.S. dollar, were allowed to float freely against each other, abandoning efforts to maintain fixed values tied to the dollar and Gold, ushering in the modern era of floating exchange rates; Also in 1973, G. Frens published refinements to the Turkevich method in Nature Physical Science (Vol. 241, pp. 20-22), improving control over particle size by varying citrate-to-Gold ratios

1973-1974 – In 1973, Fleischmann, Hendra, and McQuillan reported unexpectedly high-quality, potential-dependent Raman spectra for pyridine molecules on an electrochemically roughened Silver electrode. Martin Fleischmann and his team published their findings in 1974. This initial observation was a precursor to the discovery of Surface-Enhanced Raman Scattering (SERS)

1973-1980 – The Hunt brothers (Nelson Bunker Hunt, William Herbert Hunt, and Lamar Hunt) begin accumulating Silver holdings through futures contracts and physical purchases in order to hedge against inflation, protect their oil fortunes, and corner the market. They were able to amass over 200 million ounces of Silver, and achieve control of a huge portion of the world’s total supply. But, this attempt to corner the market backfired as price spikes, accelerated by their aggressive buying, caused exchanges to restrict buying and raise margin requirements – leading to “Silver Thursday” in 1980 with the crash of the price of Silver, from nearly $50 to around $10 an ounce, as the Hunt brothers were forced to cover their losses and liquidate their positions according to the new COMEX rules. Not only were the Hunt brothers financially ruined by this event, but many brokerage firms were, as well

1974 – In September 1974, the Fort Knox Bullion Depository broke its strict no-visitor policy to allow a group of journalists and a Congressional delegation to see the U.S. Gold reserves, addressing persistent rumors that the Gold had been removed. This rare event was organized under Mint Director Mary Brooks and Treasury Secretary William Simon to increase transparency. The Fort Knox vaults have only been opened to non-authorized visitors on three officially reported occasions in their history: 1943, 1974, and 2017; On December 31, 1974, President Gerald Ford signed Executive Order 11825, effectively ending the ban on private Gold ownership in the U.S. that had been in place since President Roosevelt’s 1933 decree, allowing Americans to legally own, buy, and sell Gold again after 41 years

1978-1980 – Gold prices surged dramatically during this period, climbing from around $226 to over $850 per ounce by early 1980, driven by soaring inflation, the Iranian Revolution (1978) disrupting oil, and geopolitical tensions caused by the Soviet invasion of Afghanistan (1979)

1980-1984 – Lithium/Silver Vanadium Oxide (Li/SVO) batteries were developed starting in 1980. The system consists of a lithium anode, a liquid organic electrolyte, a cathode composed of conductive additives, a binder, and Silver vanadium oxide, a vanadium oxide bronze produced by the thermal decomposition of vanadium oxide and Silver nitrate. While originally explored for non-medical uses, the Li/SVO batteries’ unique high-power capability and built-in state-of-charge indicator (voltage drop) made them ideal for life-saving medical devices. High rate batteries for state-of-the-art implantable cardiac defibrillators (ICDs) based on this chemistry have been under development since 1984. The first Li/SVO defibrillator battery introduced was the Model 8512 with a theoretical capacity of 5.5 Ah and dimensions of 52 mm X 33 mm X 13.5 mm. Hybrid versions (Li/CFx-SVO) emerged later

1980-1985 – ​​Sunshine Mining Co. issued two $25 million tranches of Silver-indexed bonds in 1980, creating innovative financial instruments linking debt securities to commodity prices. These bonds were exchangeable at maturity (15 years later) for either their $1,000 face value or the cash value of 50 ounces of Silver, whichever was greater. Sunshine Mining also issued a round of Silver-linked bonds in April 1985, which were linked to 58 ounces of Silver

1981 – Marc Horisberger and colleagues successfully visualized Gold nanoparticles using scanning electron microscopy (SEM), which helped establish it as a standard SEM technique, particularly in the field of immunoGold labelling; Continuing in 1981, Alexei Ekimov, working at Vavilov State Optical Institute, synthesized the first deliberately produced semiconductor quantum dots – Cadmium Selenide (CdSe) and Copper Chloride (CuCl) – in glass matrices. He demonstrated quantum size effects and quantum confinement, laying the foundation for modern quantum dot science – including that of Silver quantum dots; Finally for 1981, Günter Schmid reported synthesis of Au₅₅-phosphine clusters. The synthesis of the stable, well-defined Au₅₅-phosphine clusters in 1981 was a significant milestone in nanochemistry. The recognition and study of these properties effectively introduced the concept of quantum dots within the context of Gold nanoclusters, demonstrating that, at this scale, material behavior is dominated by quantum mechanical effects

1986-1988 – The Unipath ClearBlue home pregnancy test, first launched in 1985 (as a 30-minute test) and then as a one-step lateral flow test in 1988, was the first commercial product to use Silver nanoparticles (specifically 40-nanometer particles) conjugated to antibodies as a detection method. This technology allowed for a rapid, clear, and easy-to-use test, moving from a multi-step process to the “pee on a stick” method that became the industry standard. The use of nanoparticles in this way was a significant innovation in diagnostic technology 

1988 – Atomic force microscopy (AFM) enables measurement of individual Silver nanoparticle mechanical properties showing size-dependent hardness. This was a significant development in nanoscience, highlighting the unique, size-dependent properties that distinguish nanomaterials from their bulk counterparts; Also in 1988, the wreck of the SS Central America was located – after 131 years – 7,200 feet deep in the Atlantic Ocean. The eventual recovery from the shipwreck was over 7,000 Gold coins and hundreds of Gold ingots valued between $100-150 million. A single 80-pound (36 kg) Gold ingot recovered from the wreck, nicknamed “Eureka”, sold for a record $8 million

1990 – Researchers at the British Museum discovered that the Lycurgus Cup‘s dichroic properties resulted from Gold-Silver alloy nanoparticles embedded in the glass matrix, confirming ancient Romans‘ unintentional use of nanotechnology

1993 – Michael Giersig and Paul Mulvaney achieved the first reported synthesis and stabilization of Gold nanoparticles (AuNPs) using alkanethiols. Their work was a significant step in advancing surface chemistry control of nanoparticles and preceded the well-known Brust-Schiffrin method developed in 1994, which is a widely used two-phase synthesis method for the same purpose

1994 – Mathias Brust, Merryl Walker, Donald Bethell, David J. Schiffrin, and Robin Whyman published the Brust-Schiffrin two-phase synthesis method (Journal of the Chemical Society, Chemical Communications, pp. 801-802), using water-toluene reduction of AuCl₄⁻ by sodium borohydride in the presence of alkanethiols to produce highly stable thiol-derivatized Gold nanoparticles (AuNPs of 1-3 nm diameter) in organic solvents; Finally for 1994, Charles R. Martin at Colorado State University (CSU) develops template synthesis using track-etched polycarbonate membranes. His research demonstrated the ability to produce highly uniform nanowires – including Silver nanowires – with precisely controlled diameters as small as 10 nanometers and lengths up to 60 micrometers by electrochemically depositing materials within the pores of these membranes. He is also credited with coining the term “template synthesis” for this specific membrane-based approach

1995 – DVD technology employs germanium–antimony–tellurium or Silver-indium–antimony–tellurium phase-change alloys storing 4.7 gigabytes with multiple rewrite cycles on 120-millimeter optical discs; Robert Burrell, a biomedical engineering professor, invented the nanocrystalline Silver technology for wound dressings in 1995 while working for Westaim Corporation’s Nucryst Pharmaceuticals. The resulting product was the Acticoat dressing, which was the world’s first commercial therapeutic application of nanotechnology. The Acticoat dressing is effective against a broad spectrum of over 150 microorganisms, including Gram-positive and Gram-negative bacteria (like S. aureus), antibiotic-resistant strains (MRSA), yeast, and mold, and is considered a significant advance in wound care technology, speeding healing and fighting off infections in chronic wounds, burns, and surgical sites. Studies have shown it significantly reduces infection incidence and can improve epithelialization times in burn wounds compared to traditional Silver treatments

1995-1998 – Naomi Halas and her research group at Rice University invented metallic nanoshells in the mid-to-late 1990s, with key publications in 1998 here and here. The initial successful nanoshells were often silica core with a Gold shell, though Silver nanoshells were also developed and studied for their distinct plasmonic properties

1996 – Chad A. Mirkin and Robert L. Letsinger published A DNA-based method for rationally assembling nanoparticles into macroscopic materials (Nature, Vol. 382, pp. 607-609), demonstrating DNA-functionalized Gold nanoparticles (AuNPs) could be programmed to assemble into ordered structures. That same year, Paul Alivisatos, Kai P. Johnsson, and Peter G. Schultz, published a landmark paper in Nature detailing a method to assemble Gold nanocrystals into precise “nanocrystal molecules”, like dimers and trimers, using DNA strands as programmable linkers – a foundational step for DNA-directed nanoparticle assembly

1997 – The paper Single Molecule Detection Using Surface-Enhanced Raman Scattering (SERS) exploits the extremely large effective cross sections ( 10−17–10−16⁢cm2/molecule), available from surface-enhanced Raman scattering (SERS), to achieve the first observation of single molecule Raman scattering. Measured spectra of a single crystal violet molecule in aqueous colloidal Silver solution using one second collection time and about 2 ×105⁢W/cm2 nonresonant near-infrared excitation show a clear “fingerprint” of its Raman features between 700 and 1700⁢cm−1; Also in 1997, the paper Probing Single Molecules and Single Nanoparticles by Surface-Enhanced Raman Scattering achieves optical detection and spectroscopy of single molecules and single nanoparticles. Individual Silver colloidal nanoparticles were screened from a large heterogeneous population for special size-dependent properties, and were then used to amplify the spectroscopic signatures of adsorbed molecules

1998 – Armin Henglein demonstrates photochemical Silver nanoparticle synthesis using UV radiation, achieving 5-nanometer particles. This work was a significant milestone in the history of Silver nanoparticle research; Also in 1998, David L. Feldheim and Christine D. Keating, along with their research teams, published the paper Self-assembly of single electron transistors and related devices and demonstrated the operation of a single-electron transistor (SET) that used a 5-nanometer Silver nanoparticle as the quantum dot (Coulomb island). Their work was part of broader research into using self-assembly methods to fabricate nanoscale electronic devices

1999 – Gold falls to a 20-year low of approximately $252 per ounce. Later that year, the first Central Bank Gold Agreement, also known as “the Washington Agreement”, is signed by 15 European central banks (ECB), limiting Gold sales to 2,000 tons over five years

2000 – The paper A truncated icosahedral structure observed in Gold nanoparticles describes a new type of Gold nanoparticle. The particle shape corresponds to a truncated icosahedron which in some orientations appears as an asymmetric decahedron. The particle structure is discussed and the corresponding high resolution electron microscopy images are calculated for the optimum defocusing condition in several orientations; Also in 2000, China’s Ministry of Science and Technology allocates 2 billion yuan ($250 million) to National Nanotechnology Initiative with Silver nanowire research designated as priority area, establishing 15 dedicated research centers across Beijing, Shanghai, and Shenzhen; That same year, T. Andrew Taton, Chad Mirkin, and Robert Letsinger developed scanometric DNA array detection using nanoparticle probes (Science, Vol. 289, pp. 1757-1760), where they described a method for analyzing DNA arrays using oligonucleotide-modified Gold nanoparticle probes and a conventional flatbed scanner. This research was a key development in biosensing applications, leading to the creation of commercial diagnostic systems like the Luminex Verigene System

2001 – The paper Ultrathin Single-Crystalline Silver Nanowire Arrays Formed in an Ambient Solution Phase reports the synthesis of single-crystalline Silver nanowires of atomic dimensions. The ultrathin Silver wires with 0.4 nanometer width grow up to micrometer-scale length, inside the pores of self-assembled calix[4]hydroquinone nanotubes, by electro-/photochemical redox reaction in an ambient aqueous phase, and are very stable under ambient air and aqueous environments

2002 – A highly publicized 1933 Double Eagle Gold coin, once part of Egypt‘s King Farouk‘s collection, was legally auctioned by Sotheby‘s for $7.59 million (including fees and monetization), becoming the most valuable coin sold at auction, with $3 million in proceeds going to the U.S. Treasury. The U.S. Mint struck 445,000 of these $20 Gold coins in 1933, but President Roosevelt‘s decision to take the U.S. off the Gold standard meant they were never released into circulation and were ordered melted down. The specific coin sold in 2002 was one of several that disappeared and were later found in King Farouk’s collection. After being recovered by the Secret Service, its ownership was disputed for years until a settlement allowed for this historic auction, establishing its unique legal status; Also in 2002, Younan Xia’s group at University of Washington published the paper Large-Scale Synthesis of Uniform Silver Nanowires Through a Soft, Self-Seeding, Polyol Process, which introduces a novel and simple constituent-template displacement process to incorporate nanosized particles into MSTFs. A self-seeding process is used to generate bicrystalline Silver nanowires by reducing AgNO3 with ethylene glycol at ∼160 °C. Uniform Silver nanowires were routinely synthesized with diameters of ∼60 nm and lengths up to ∼50 μm. Later in 2002, Younan Xia and group published the article Shape-Controlled Synthesis of Gold and Silver Nanoparticles in Science Magazine, in which they formalized the polyol synthesis method (reduction of Silver in hot ethylene glycol) and demonstrated the production of Silver nanowires with polyvinylpyrrolidone (PVP) as a capping and shape-directing agent, achieving 90% yield. Xia and his group extended their research in 2003, and this method became an industry standard for Silver nanowire production; Finally in 2002, Mirkin’s group produced the paper Nanoparticles with Raman Spectroscopic Fingerprints for DNA and RNA Detection (Science, Vol. 297, pp. 1536-1540), in which Gold nanoparticles (AuNPs) were the core for their DNA/RNA detection probes, then coated with Silver to create a surface-enhanced Raman scattering (SERS) promoter for Raman-active dyes

2003 – The paper Polyol Synthesis of Uniform Silver Nanowires:  A Plausible Growth Mechanism and the Supporting Evidence, from Xia’s group (see 2002), discusses growth mechanisms for the large-scale synthesis of Silver nanowires with uniform diameters and proposes that Silver nanowires evolve from a twinned nanoparticle (MTP) of Silver with the assistance of PVP at the initial stage of the Ostwald ripening process; Finally in 2003, the SARS outbreak drives increased demand for Silver antimicrobial coatings in hospital equipment and air filtration systems as healthcare facilities implement infection control measures

2004 – The second Central Bank Gold Agreement is signed, raising the annual sales limit to 500 tonnes. This agreement, also known as the “Washington Agreement on Gold”, helped stabilize the Gold market by coordinating sales among European central banks and providing market transparency; Also in 2004, the paper Polyol Synthesis of Silver Nanoparticles:  Use of Chloride and Oxygen to Promote the Formation of Single-Crystal, Truncated Cubes and Tetrahedrons demonstrates the preparation of single-crystal cubes and tetrahedrons of Silver with truncated corners/edges for the first time in high yields, achieved by reducing Silver nitrate with ethylene glycol heated to 148 °C in the presence of poly(vinyl pyrrolidone) and a trace amount of sodium chloride. These Silver nanoparticles were relatively monodisperse in size and shape, and their dimensions could be readily controlled in the range of 20 to 80 nm by varying the reaction time and other experimental parameters. The study proposes that the defects inherent in twinned nuclei of Silver led to their selective etching and dissolution by chloride and oxygen (from air), leaving only the single crystalline ones to grow into nanoscale cubes and tetrahedrons; Continuing in 2004, the paper High-Density Silver Nanoparticle Film with Temperature-Controllable Interparticle Spacing for a Tunable Surface Enhanced Raman Scattering Substrate demonstrates the formation of high-density Silver nanoparticles for a tunable surface enhanced Raman scattering substrates. The SERS spectra of Rhodamine 6G on a high-density Silver particle film at various temperatures is characterized to demonstrate the tunable plasmon coupling between high-density nanoparticles; Finally for 2004, according to the paper DNA-templated Ag nanocluster formation, the high affinity of Ag+ for DNA bases has enabled creation of short oligonucleotide-encapsulated Ag nanoclusters without formation of large nanoparticles. Time-dependent formation of cluster sizes ranging from Ag1 to Ag4/oligonucleotide were observed with strong, characteristic electronic transitions between 400 and 600 nm

2005 – The first report of synthesizing Silver nanorods on single-stranded DNA (ssDNA) as a template was published in a paper by Gang Wei et al. in May 2005. The paper, titled One-Step Synthesis of Silver Nanoparticles, Nanorods, and Nanowires on the Surface of DNA Network, described a method to control the shape and size of Silver nanostructures by using the DNA network as a soft template. Silver ions were adsorbed onto the DNA network and then reduced with sodium borohydride to form Silver nanoparticles, nanorods, and nanowires; Also in 2005, the Samsung Advanced Institute of Technology (SAIT) documented the release of Silver ions from Silver nanowires at concentrations of 0.1-1.0 ppb, which resulted in a 99.9% bacterial kill rate against E. coli and Staphylococcus aureus within two hours, enabling antimicrobial coating applications. This finding was a significant step toward the industrial adoption of nanoSilver technology. That same year, Samsung released SilverCare washing machines using Silver nanoparticle-releasing electrodes (Silver Nano Health System), producing 5-10 ppb Silver ions for antibacterial action. The technology involved applying an electric current to two Silver plates to release Silver ions (claimed to be nanoparticles, or a quarter of a nanometer in diameter) into the wash water to kill bacteria and provide an antibacterial coating on clothes. The technology was subsequently rolled out to other appliances like refrigerators and air conditioners. The US Environmental Protection Agency (EPA) later determined these machines were subject to pesticide regulations because of the germ-killing claims

2006 – Barclays launches iShares Silver Trust ETF on April 28, providing investors direct Silver exposure without physical storage requirements; In November and December 2006, the Environmental Protection Agency (EPA) announced its decision to require the registration of Silver nanoparticle products as pesticides under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) when they are marketed with antimicrobial claims. Prior to this decision, many products containing nanoSilver were often classified simply as “devices” and were not subject to EPA registration requirements. However, in late 2006, the EPA clarified its position, stating that any substance or product that makes claims to disinfect, sanitize, reduce, or mitigate the growth of microorganisms must be registered as a pesticide. The specific catalysts for this announcement were consumer products like the Samsung “SilverCare” washing machine, which was advertised as using Silver ions to kill bacteria. The EPA determined that the generation and release of Silver ions for this express pesticidal purpose required FIFRA registration. This action marked a significant moment in the regulation of nanotechnology-based consumer products; Also in 2006, the paper Shape-Controlled Synthesis of Metal Nanostructures: The Case of Silver discussed the concept of shape-controlled synthesis by investigating the growth mechanisms for Silver nanocubes, nanowires, and nanospheres produced through a polymer-mediated polyol process. Experimental parameters, such as the concentration of AgNO(3) (the precursor to Silver), the molar ratio between poly(vinylpyrrolidone) (PVP, the capping agent) and AgNO(3), and the strength of chemical interaction between PVP and various crystallographic planes of Silver, were found to determine the crystallinity of seeds (e.g., single crystal versus decahedral multiply twinned particles). In turn, the crystallinity of a seed and the extent of the PVP coverage on the seed were both instrumental in controlling the morphology of the final product. The ability to generate Silver nanostructures with well-defined morphologies provides a great opportunity to experimentally and systematically study the relationship between their properties and geometric shapes

2007 – Global Silver production reaches approximately 21,100 metric tons, equivalent to 678.4 million ounces of Silver, annually, with Mexico, Peru, and China as leading producers. The United States accounted for 6% of this production, producing 1,260 metric tons. China emerging as the top Gold producer that same year, producing 276 metric tons (9.7 million ounces), surpassing South Africa’s 272 metric tons, and the total global supply of Gold in 2007 was 3,910 metric tons; Also in 2007, the paper Synthesis of Silver Nanostructures with Controlled Shapes and Properties demonstrates that, by controlling the crystallinity of the seeds from which nanostructures grow, and the rate of atomic addition to seeds, selectively produced pentagonal nanowires, cuboctahedra, nanocubes, nanobars, bipyramids, and nanobeams of Silver are achieved. The example of nanobars illustrates how the shape of a Silver nanostructure affects the color of light that it scatters. The study further shows how Silver nanowires and nanobeams can serve as conduits for both electrons and photons; Finally in 2007, the paper Strongly emissive individual DNA-encapsulated Ag nanoclusters as single-molecule fluorophores presents water-soluble, near-IR-emitting, DNA-encapsulated Silver nanoclusters that exhibit extremely bright and photostable emission on the single-molecule and bulk levels. These represent significant improvements over existing dyes, and the nonpower law blinking kinetics suggest that these very small species may be alternatives to much larger and strongly intermittent semiconductor quantum dots

2008 – Beijing Olympics deploys Silver nanoparticle photocatalytic coatings (30-50 nanometer particles on TiO2) for air purification in indoor venues; The 2008-2009 financial crisis drives increased Gold and Silver investment demand as investors seek inflation hedges during banking system collapse and government monetary expansion programs, with the high price per ounce for Silver reaching approximately $20 and the high price per ounce for Gold reaching approximately $1,000; Digital photography’s market dominance eliminates traditional photographic film demand, reducing annual Silver consumption from peak 1999 levels; The paper Inkjet printing of 3D metal–insulator–metal crossovers describes the inkjet printing of both a commercial Silver nanoparticle metal and a cationic/thermally cured epoxy insulator, SU8, and discuss the role of print strategy and surface treatment on retaining functionality

2009 – The third Central Bank Gold Agreement (CBGA3) reduced the annual sales limit for participating central banks to 400 tonnes of Gold, with a total limit of 2,000 tonnes, over the agreement’s five-year duration (2009-2014). This was a significant reduction from the 500 tonnes per year limit set in the second agreement (CBGA2). The agreement was extended by 19 European central banks, the European Central Bank, and other institutions like the US, Japan, and Australia, and the IMF, although not a signatory, noted its sales could fit within these limits. The agreement aimed to bring stability and predictability to the Gold market by limiting official sector sales, which was seen as positive for Gold prices; Also in 2009, the study Stepwise Growth of Decahedral and Icosahedral Silver Nanocrystals in DMF detailed the stepwise growth mechanism of decahedral and icosahedral Silver nanoparticles from tetrahedral units using N,N-dimethylformamide (DMF) solution; Continuing in 2009, the paper RFID Tag Antenna Utilizing Ink-Jet Printing Technology uses a nano Silver ink to demonstrate different configurations, along with their measured performances; Finally in 2009, the paper Silver Nanowire Networks as Flexible, Transparent, Conducting Films: Extremely High DC to Optical Conductivity Ratios demonstrates aqueous dispersions of Silver nanowires to prepare thin, flexible, transparent, and uniform conducting films, achieving the highest conductivity ratio ever observed for nanostructured films

2010 – The paper Synthesis of Silver nanostructures of varying morphologies through seed mediated growth approach reports a method to synthesize Silver nanoparticles of varying morphologies by a seeding growth approach at room temperature. Seeds are prepared by reducing Silver nitrate with sodium borohydride, and trisodium citrate is used as capping agent

2010-2013 – EU Regulation 1223/2009, effective from 2010, established rules for nanomaterials, requiring safety assessments, pre-market notification (via CPNP), and mandatory labeling (using “[nano]”) for substances like Silver nanoparticles (Colloidal Silver) in cosmetics by 2013, though the full scientific guidance evolved over time

2011 – Silver and Gold prices continued to surge following the 2008-2009 financial crisis, “the Great Recession”, fueled by loose monetary policies (quantitative easing) and the European debt crisis, with the high price per ounce for Silver reaching approximately $48.70 and the high price per ounce for Gold reaching approximately $1,900

2012 – The paper Thousand-fold Enhancement of Single-Molecule Fluorescence Near a Single Gold Nanorod reports large enhancements of single-molecule fluorescence up to 1100 times by using synthesized Gold nanorods. This high enhancement is achieved by selecting a dye with its adsorption and emission close to the surface plasmon resonance of the Gold nanorods; Also in 2012, the paper Quantum confinement in Silver selenide semiconductor nanocrystals discusses Ag2Se nanocrystals, with average diameters between 2.7 and 10.4 nm, that exhibit narrow optical absorption features in the near to mid infrared, and demonstrates that these features are broadly tunable due to quantum confinement. They provide the longest wavelength absorption peaks (6.5 μm) yet reported for colloidal nanocrystals; That same year, the paper In vivo fluorescence imaging with Ag2S quantum dots in the second near-infrared region demonstrates synthesized Ag(2)S quantum dots (QDs) with bright near-infrared-II fluorescence emission (around 1200 nm), and six-arm branched PEG surface coating, for in vivo small-animal imaging. The 6PEG-Ag(2)S QDs afforded a tumor uptake of approximately 10% injected dose/gram; Finally for 2012, the paper Ag2S quantum dot: a bright and biocompatible fluorescent nanoprobe in the second near-infrared window demonstrates Ag(2)S quantum dots (QDs) as a promising fluorescent probe with both bright photoluminescence and high biocompatibility for the first time. The results of the study opened possibilities of using biocompatible Ag(2)S QDs for in vivo anatomical imaging and early stage tumor diagnosis with deep tissue penetration, high sensitivity, and elevated spatial and temporal resolution owing to their high emission efficiency in the unique NIR-II imaging window

2013 – The paper Facile Synthesis of Highly Photoluminescent Ag2Se Quantum Dots as a New Fluorescent Probe in the Second Near-Infrared Window for in Vivo Imaging reports a facile solvothermal method to synthesize highly photoluminescent Ag2Se quantum dots (QDs) with emission at 1300 nm in the second near-infrared window. After surface modification of C18-PMH-PEG, the Ag2Se QDs possess bright photoluminescence, good water-solubility, high colloidal stability and photostability, as well as decent biocompatibility, which are further successfully performed in deep imaging of organs and vascular structures with high spatial resolution. This new NIR-II fluorescent nanoprobe with small sizes, ideal optical properties, and decent biocompatibility opens up exciting opportunities for future biomedical applications; Also in 2013, researchers at the University of Illinois at Urbana-Champaign (UIUC) created revolutionary nano-scale Lycurgus Cup arrays, essentially billions of tiny cups with metal nanoparticles, achieving 100x greater sensitivity for detecting chemicals, DNA, and proteins by using nanoplasmonics and turning sensing into a visible color change (colorimetric sensing). Inspired by the ancient Lycurgus Cup’s optical properties, this breakthrough used both Gold and Silver nanoparticles and allowed for simpler, naked-eye detection, paving the way for portable, lab-on-a-chip applications in health and environmental monitoring; Continuing for 2013, the paper Green Synthesis of Silk Fibroin-Silver Nanoparticle Composites with Effective Antibacterial and Biofilm-Disrupting Properties demonstrates natural polymer Bombyx mori silk fibroin used as a biotemplate to produce Silver nanoparticles in situ under light (both incandescent light and sunlight) at room temperature – an environment-friendly and energy-saving approach. The silk fibroin-Silver nanoparticle composite prepared by this clean and facile method is expected to be an effective and economical antimicrobial material in biomedical fields; Finally for 2013, the paper Silver Nanowire Transparent Electrodes: Fabrication, Characterization, and Device Integration demonstrates the fabrication of Silver nanowire electrodes on glass substrates with a low sheet resistance and 90% optical transparency at 550 nm. These resistance and transparency values match that of commercially available indium tin oxide, are superior to other alternatives such as carbon nanotube electrodes, and are low cost and easy to fabricate

2014 – The fourth Central Bank Gold Agreement (CBGA4) was signed and announced on May 19, 2014, by the European Central Bank (ECB) and 20 other European central banks. Unlike earlier agreements, CBGA4 removed specific sales limits, focusing instead on coordinating transactions to avoid market disruption and noting no plans for significant Gold sales at the time. It was a five-year agreement, and the signatories chose not to renew it when it expired in 2019; In 2014, the paper Resonant plasmonic enhancement of single-molecule fluorescence by individual Gold nanorods studies fluorescence enhancement by isolated Gold nanorods, which can be cheaply synthesized in large volumes, and explores the role of the surface plasmon resonance (SPR) on the observed enhancements. The study finds that the fluorescence of a weak emitter, crystal violet, can be enhanced more than 1000-fold by a single Gold nanorod with its SPR at 629 nm excited at 633 nm; Also in 2014, the paper Enhancing single-molecule fluorescence with nanophotonics introduces the basic concepts of nanophotonic devices such as zero mode waveguides and nanoantennas, highlighting Gold and Silver nanostructures, current applications, and the future potential of nanophotonic approaches when combined with biological systems and single-molecule spectroscopy; Finally in 2014, the paper Synthesis of Silver Nanostructures by Multistep Methods introduces three typical multistep methods to prepare Silver nanostructures with well-controlled shapes, including the double reductant method, the etching technique, and the construction of core-shell nanostructures. The three methods can not only prepare various Silver nanostructures with well-controlled shapes, which exhibit unique optical properties, such as strong surface-enhanced Raman scattering (SERS) signal and localized surface plasmon resonance (LSPR) effect, but also have potential application in many areas

2015 – The solar panel industry consumes approximately 60 million ounces of Silver as global photovoltaic annual installations reach 51 gigawatts capacity, with Silver paste essential for cell electrical contacts and energy conversion; Also in 2015, the paper Bromide (Br) – Based Synthesis of Ag Nanocubes with High-Yield reports a modified polyol Silver (Ag) nanocube synthesis approach focused on bromide ion (Br− ions) concentration tuning, finding that higher concentration of Br− ions can enhance oxidative etching effects, which is the dominative factor in determining nanostructure geometry

2016 – The paper Silver Nanowire-IZO-Conducting Polymer Hybrids for Flexible and Transparent Conductive Electrodes for Organic Light-Emitting Diodes considers solution-processed Silver nanowires (AgNWs) as a promising material for next-generation flexible transparent conductive electrodes. The fabricated electrodes exhibited a low sheet resistance of 5.9 Ωsq−1 with high transmittance of 86% at 550 nm

2017 – Tesla Model 3 electric vehicles employ 25-55 grams of Silver in electrical systems, including battery connections and motor components, creating new Silver demand in the automotive sector; Also in 2017, Treasury Secretary Steve Mnuchin and Congressional representatives become the second group to visit Fort Knox vaults. The 2017 visit by Mnuchin and others also occurred amidst questions about the Gold’s presence, confirming for them that the reserves were intact. The Fort Knox vaults have only been opened to non-authorized visitors on three officially reported occasions in their history: 1943, 1974, and 2017; The paper Transparent Electrodes Based on Silver Nanowire Networks: From Physical Considerations towards Device Integration presents the main properties of AgNW based transparent electrodes, as well as some considerations relating to their efficient integration in devices. The influence of network density, nanowire sizes, and post treatments on the properties of AgNW networks are also evaluated; Continuing for 2017, in the study Combined Inkjet Printing and Infrared Sintering of Silver Nanoparticles using a Swathe-by-Swathe and Layer-by-Layer Approach for 3-Dimensional Structures, an ink containing AgNPs was printed using a bespoke 3D multimaterial IJP system, JETx, and subsequently sintered using a built-in IR source. Two distinct sintering methods, swathe-by-swathe (SS) and layer-by-layer (LS) were employed to sinter the AgNP ink; Finally in 2017, the paper Recent Advances in Cancer Therapy Based on Dual Mode Gold Nanoparticles provides an overview of the use of functionalized Gold nanoparticles for cancer therapy and reviews many recent advances on the use of Gold NPs in PTT, RT and PTT/RT based on different types of AuNPs, irradiation conditions, and protocols

2018 – The paper Cohesively enhanced electrical conductivity and thermal stability of Silver nanowire networks by nickel ion bridge joining reports a facile method for producing high-performance nickel enhanced Silver nanowire (Ag NW) transparent electrodes on a flexible substrate

2019 – The paper Controlled Synthesis of Silver Nanostructures Using Polyol Methods presents results from a series of studies aimed at developing methods to achieve better control of the synthesis of Silver nanostructures using the polyol method – a method which has shown great potential as a controllable, low-cost, and large-scale means to synthesize various Silver nanostructures. The production, stability, and growth of Ag NP seeds are at the center of Silver nanostructure synthesis, and Ag NP seed preparation and growth were studied separately to provide detailed insight on the reaction mechanism; Also in 2019, the paper Silver Selenide Colloidal Quantum Dots for Mid-Wavelength Infrared Photodetection presents the fabrication and characterization of Ag2Se colloidal quantum dot-based photoconductive photodetectors, with results suggesting that further enhancement in performance could be achieved through accurate control of carrier concentration. With this improvement, Ag2Se colloidal quantum dots may serve as a promising mid-wavelength infrared absorber for the development of thermal infrared sensors and imagers with low size, weight, power consumption, and cost; Continuing for 2019, the paper Synthesis of Silver nanoparticles with different shapes presents an overview of the shape-controlled synthesis of Silver nanoparticles using the various methods to-date; Finally in 2019, the paper Bioinspired Unidirectional Silk Fibroin-Silver Compound Nanowire Composite Scaffold via Interface-Mediated In Situ Synthesis reports that unidirectional silk fibroin scaffold can not only act as a carrier, but also serve as a controllable multiscale reactor to achieve the in situ synthesis of a Ag3 PO4 nanowire network anchored to ordered channels. Both the silk fibroin matrix and the interface play important roles in the nucleation and growth of the Ag3PO4 nanowires. It is expected that this method can be extended to fabricate a series of silk-based unidirectional composite scaffolds with varying functionalities

2020 – COVID-19 pandemic drives Silver antimicrobial surface demand, as facilities implement enhanced disinfection protocols, and also drives HeiQ Viroblock NPJ03 (Swiss textile treatment with 1-2% Silver nanoparticles) achieving 99.99% SARS-CoV-2 reduction in 30 minutes; Also in 2020, global Silver production declines to 780 million ounces as mining operations face pandemic-related shutdowns and safety restrictions (a 6-7% decline from the previous year); The highest price for Gold in 2020 was around $2,070 per ounce, reaching a then-record high in early August due to pandemic-driven economic uncertainty, low interest rates, and significant stimulus packages. For the same reasons, Silver reached nearly $30 on August 6, 2020; The paper The Fluorescent Palette of DNA-Templated Silver Nanoclusters for Biological Applications provides an overview of DNA-AgNCs from the viewpoints of synthesis and fluorescence properties, and summarizes its biological applications of fluorescence sensing and imaging; Also in 2020, the paper Green Synthesis of Silver Nanoparticles: An Eco-Friendly Approach summarizes the scientific reports in the eco-friendly synthesis arena of Ag NPs and their applications in the biomedical field

2021 – The Reddit WallStreetBets community attempts Silver short squeeze in late January-early February, briefly pushing prices above $30 per ounce through coordinated physical Silver purchasing and SLV ETF investments; In 2021, the paper Anisotropic Silver Nanomaterials by Photochemical Reactions: Synthesis and Applications reviews the main factors affecting the synthesis of anisotropic Silver nanoparticles, such as irradiation wavelength, pH, etc., and the role of specific key molecules, such as citrate; Continuing for 2021, the paper Plant-Based Green Synthesis of Nanoparticles: Production, Characterization and Applications provides an overview of current trends in green synthesis, characterization, and applications of a range of plant-derived Silver NPs; Also in 2021, the paper Silver nanoparticles synthesized using leaf extract of Azadirachta indica exhibit enhanced antimicrobial efficacy than the chemically synthesized nanoparticles: A comparative study provides a detailed and systemic study of two different synthesis routes for Ag-NPs, that is, the chemical and the biological. Ag-NPs were synthesized chemically (cAg-NPs) using a chemical reductant and biologically (bAg-NPs) by using aqueous leaf extract of Azadirachta indica (neem). The synthesized nanoparticles were characterized using UV-visible spectrophotometry, FT-IR, EDX, and TEM. The results revealed that bAg-NPs of APS 43 nm were highly antimicrobial against both the tested bacterial stains followed by cAg-NPs of 8 nm; And in 2021, the paper ​​Graphdiyne‐Stabilized Silver Nanoparticles as an Efficient Electrocatalyst for CO2 Reduction reports in‐situ synthesized uniform Ag nanoparticles (AgNPs) directly growing on the surface of two‐dimensional graphdiyne (GDY) for selectively reducing CO2 to CO with high efficiency and stability. Due to the special electronic distribution of GDY, it can not only serve as a template for the growth of AgNPs to prevent its aggregation, but also increase active sites and transformation of electrons through the intimate interaction between phase interface to enhance their cooperative catalytic effect, which highly improves the electrocatalytic performance of the nanocomposite; Finally for 2021, the paper Direct Printed Silver Nanowire Strain Sensor for Early Extravasation Detection presents a wearable sensor patch for the early detection of extravasation by using a simple, direct printing process. Silver nanowire (AgNW) ink was first formulated to provide necessary rheological properties to print patterns on flexible plastic sheets. By adjusting printing parameters, alignments of AgNWs in the printed patterns were controlled to enhance the resistance change under stretching conditions. A resistive strain-sensing device was then fabricated by printing patterned electrodes on a stretchable film for skin attachment. Sensors of millimeter size were printed in an array and were used for multiple detection points in a large area to detect extravasation at small volumes (<0.5 mL) at accurate bump location

2022 – The Russia-Ukraine conflict disrupts global Silver supply, with Russia producing approximately 45 million ounces annually. And, Russian platinum and palladium export restrictions force Silver nanowire manufacturers to reformulate catalyst systems, with polyol process yields temporarily declining from 92% to 78% before alternative ruthenium catalysts restore efficiency; Also in 2022, global solar panel installations consume approximately 118-140 million ounces of Silver, representing approximately 13% of total annual production; In 2022, the paper Silver Nanoparticles for Conductive Inks: From Synthesis and Ink Formulation to Their Use in Printing Technologies reviews the different methods to obtain Ag NPs, their use in the preparation of stable dispersion of inks depending on the printing method, and the post-processing of printed patterns for obtaining high electrical conductivity. Formulation of Silver inks and formation of conductive patterns by using different printing techniques (inkjet printing, screen printing and aerosol jet printing) are presented; Also in 2022, the paper Scalable Production of High-Quality Silver Nanowires via Continuous-Flow Droplet Synthesis applies continuous-flow synthesis for the scalable and high-quality production of Ag NWs. With an optimized synthetic formula, a mass production of pure Ag NWs of 36.5 g/h was achieved by a multiple-channel, continuous-flow reactor; Continuing for 2022, the paper Green Route Synthesis and Characterization Techniques of Silver Nanoparticles and Their Biological Adeptness discusses the green routes to synthesize AgNPs that have established effective applications in various areas, including biosensors, magnetic resonance imaging (MRI), cancer treatment, surface-enhanced Raman spectroscopy (SERS), antimicrobial agents, drug delivery, gene therapy, DNA analysis, etc.; Finally for 2022, the paper Gold Nanoparticle-Mediated Lateral Flow Assays for Detection of Host Antibodies and COVID-19 Proteins reviews GNP-based LFAs used for either COVID-19 proteins or human response antibodies

2023 – Mexico produces 202 million ounces of Silver, maintaining position as world’s largest producer, followed by China at approximately 109 million ounces (3,400 metric tons) and Peru at approximately 99 million ounces (3,100 metric tons); In 2023, the paper Elucidating the role of seed structure in the heterometallic seeded growth of copper-based nanocrystals discusses the role of surface ligands and crystallinity of Gold nanocrystal seeds on the heterometallic seeded growth of Cu-based nanocrystals and illustrates the importance of precise control of seed characteristics for the predictive synthesis of structurally complex multimetallic nanocrystals; Also in 2023, the paper Printable Silver Nano Ink for Bendable Ultrawideband Antenna with Triple-Notch Characteristics describes the application of a printable Silver nanoparticle-based ink for rapidly fabricating an antenna with bendable and triple-notch characteristics designed for UWB communication systems. The ink, composed of monodisperse Silver nanoparticles, isopropanol, and ethyl glycol, can easily produce favorable conductive patterns at a sintering temperature below 130 °C after inkjet printing; Finally for 2023, the paper Breaking the Limit of Size-Dependent CO2RR Selectivity in Silver Nanoparticle Electrocatalysts through Electronic Metal–Carbon Interactions demonstrates that electronic metal–support interactions (EMSIs) between Silver and carbon can dramatically improve the CO2 reduction reaction (CO2RR) performance of the small Ag nanoparticles

2024 – In 2024, Gold reached record highs, breaking $2,700/oz and hitting peaks around $2,748 per ounce in late October, driven by Fed rate cuts, Middle East conflict between Israel and Iran, and US election uncertainty, with a significant rally in Q4. This marked a substantial increase from early 2024’s $2,063 level, establishing new records and attracting major central bank and investor interest. Meanwhile, the spot price for Silver reached highs not seen in over a decade, peaking around $34.85 per troy ounce in October, driven by economic uncertainty, increased demand for its industrial uses (especially solar), and parallel rallies with Gold, despite some volatility with the US dollar and interest rate speculation. The year saw Silver climb from the low $20s to break the $30 mark in May and again in September, with a strong finish driven by geopolitical factors and strong demand; The global Silver nanoparticle market, specifically, reached $3.2 billion, with medical applications (40%), electronics (25%), textiles (20%), and catalysis (15%) as primary sectors; By 2024, the majority of global public health problems are now treated with green synthesized Silver nanoparticles (AgNPs), according to the paper A systematic review on green synthesis of Silver nanoparticles using plants extract and their bio-medical applications, which discusses extensively the biogenic synthesis of Silver nanoparticles (AgNPs), using various plants, and their applications in antibacterial, antifungal, antioxidant, anticancer, anti-inflammatory, and antidiabetic activities. The characterization of AgNPs, possibility of preparing AgNPSs with different shapes using biological method and their impact on functions and toxicities, impact of size, shape and other properties on AgNPs functions and toxicity profiles, limitations, and future prospects of green-mediated AgNPs have also been reported in this study; Also in 2024, the paper Dedoping of Intraband Silver Selenide Colloidal Quantum Dots through Strong shows that the small molecular p-type dopant 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ) can be used to extract electrons from the 1Se state of MWIR active Ag2Se CQDs to activate their intrinsic energy gap in the SWIR window, demonstrating doping mechanisms that involve an integer charge transfer akin to doping in semiconducting polymers. These indications of charge transfer are promising milestones on the path to achieving sustainable SWIR Ag2Se CQD photodetectors; And, the paper Silver Nanowire-Based Flexible Strain Sensor for Human Motion Detection presents the design and fabrication of a flexible strain sensor based on Silver nanowires, demonstrating great potential for future multifunctional wearable electronic devices; Continuing for 2024, the paper Silver Telluride Colloidal Quantum Dot Solid for Fast Extended Shortwave Infrared Photodetector presents a novel eSWIR photodetector that is fabricated using Silver telluride (Ag2Te) CQDs. The best eSWIR Ag2Te CQD photodetector exhibits a fall time of 72 ns, representing the fastest response time among all prior CQD-based eSWIR photodetectors, including those containing toxic elements, such as Pb and Hg; For Gold nanoparticles in 2024, the paper Weakly ionized Gold nanoparticles amplify immunoassays for ultrasensitive point-of-care sensors investigates surface chemistry on the sensitivity of AuNP LFIAs. By modifying surface ligands, a surface chemistry strategy involving weakly ionized AuNPs enables ultrasensitive naked-eye LFIAs (~100-fold enhanced sensitivity). The surface chemistry using weakly ionized AuNPs represents a versatile approach for sensitizing POC sensors; Finally for 2024, the paper Gold nanoparticle–based lateral-flow immunochromatographic biosensing assays for the diagnosis of infections presents the principles and history of ICA use for the diagnosis of infections, and discusses the prospects for using Gold nanoparticles in the ICA, presenting data on the methods used to make and conjugate Gold nanoparticles, as well as the effect of particle size and shape on ICA sensitivity

2025 – The high price for Gold in 2025 reached record levels, peaking above $4,300 per ounce by early December, driven by geopolitical instability, high US government debt, a weakening dollar, anticipated Fed interest rate cuts, and central bank buying, with some experts predicting a rise towards $5,000 as investors sought safe-haven assets amidst economic uncertainty. The highest Silver rate in 2025 was a record high around $59 per troy ounce, hit in early December, driven by strong safe-haven demand, industrial use in green tech (EVs, solar), central bank policies, and a persistent supply deficit, making it a landmark year with over 100% gains for the metal; Also in 2025, urban mining operations continue developing bacterial bioleaching processes for electronic waste Silver recovery, with recycling providing approximately 180-193 million ounces of secondary Silver supply; For scientific discoveries in 2025, the paper Unconventional seed-mediated growth of Silver with a macromolecular NHC-Ag precursor introduces a “new” Frank-van de Merwe growth mode of Ag – achieved using a macromolecular N-heterocyclic carbene-Ag(I) (NHC-Ag) complex; That same year, the paper Phosphine-Free Synthesis of Monodisperse and Size-Tunable Silver Selenide Quantum Dots via Thermo-Regulated Selenium Dioxide Reactivity for High-Efficiency NIR-II Emission demonstrates a thermo-regulated synthetic strategy for size-tunable Ag2Se QDs employing safe and cost-effective SeO2 as the Se precursor. Furthermore, with an Au alloying strategy, tunable NIR-II emission (950–1250 nm) with a record-high PL QY of 53.59% at 1140 nm is successfully achieved, along with superior photostability, paving the way for eco-friendly Ag-chalcogenide QDs toward applications in biological and infrared optoelectronics; Also in 2025, the paper Heavy Metal Free Ag2Se Quantum Dot Inks for Near to Short-Wave Infrared Detection reports high-performance, heavy-metal-free Ag2Se cQD photodetectors, utilizing a solution phase ligand exchange (SPLE), which eliminates the need for the multistep layer-by-layer depositions used in conventional solid-state ligand exchange approaches, and also demonstrates a self-powered photodiode, achieving a specific detectivity of 6.5 × 1010 Jones at 1200 nm, with a 3 dB bandwidth of 18 kHz and sub-50 μs response times, rivaling those of other heavy-metal-free cQDs. This work positions Ag2Se cQDs as a viable, regulatory compliant alternative for near- to short-wave IR detection and offers a strategy for improving performance in larger Ag2Se cQDs active in the midwave IR regime; And, the paper Hydrothermal microwave synthesis of water soluble NIR-II emitting Ag2S quantum dots demonstrates a novel microwave-assisted, hydrothermal, approach to the the synthesis of Silver sulphide (Ag2S) QDs, exhibiting NIR emission spanning the biological transparency windows via modulation of the reaction parameters and paving the way for the development of safer QDs suitable for future clinical applications

4. Final Thoughts

Is it a strange historical irony that gold and silver became more valuable and more essential to human civilization even as they shed the monetary roles they had played for five millennia, or is the irony rather that human beings should be surprised to find new purpose for these ancient elements, formed billions of years ago, beyond the base societal need of economic transaction?

Maybe the story of Gold and Silver in the modern era is more the story of human behavior than it is the story of how materials transcended their original purposes.

Looking forward, it seems likely that Gold and Silver, the metals that structured ancient trade routes, financed empires, and backed currencies for millennia, will continue finding new purposes in this new Industrial Revolution – even as human motivation remains the same: the desire to control.

Thanks for reading!

5. Appendix

Here are some other articles on Gold you may enjoy:

• A History Of Gold In The Middle Ages – here.
• A History Of Gold In The Early-Modern Era – here.
• A History Of Gold In The Modern Era – here.
• A Complete History Of Gold: From Prehistory To The Modern Era – here.
• 49 Interesting Facts About Gold – here.
• Why Is Gold At The Base Of Exter’s Inverted Pyramid Of Risk? Counterparty Risk – here.
• What’s The State Of Gold Nanoparticles (AuNPs) Materials Innovation In 2025? – here.

Here are some other articles on Silver you may enjoy:

• A History Of Silver In The Middle Ages – here.
• A History Of Silver In The Early-Modern Era – here.
• A History Of Silver In The Modern Era – here.
• A Complete History Of Silver: From Precious Metal To Industrial Necessity – here.
• 58 Things You Might Not Know About Silver – here.
• What Are Silver Quantum Dots? A Complete History From Faraday To Quantum Photonics – here.
• What Are Silver Nanowires? A Complete History From Feynman To Industrial Adoption – here.
• A History Of Silver Nanoparticles: From Victorian-Era Curiosity To Quantum Frontiers – here.