Silver is a precious metal that has been highly valued throughout human history for its beauty, monetary value, and applications in industry. With its bright white luster, high electrical and thermal conductivity, and anti-microbial properties, silver has become an indispensable resource for jewelry, currency, electronics, photography, and more. But how abundant is silver on Earth? Where is it located, and how is it produced?
Key Facts About Earth’s Silver Supply
- Total estimated worldwide reserves: 530,000 metric tons
- Top 3 countries with largest silver reserves: Peru, Poland, Chile
- Annual worldwide mining production: ~27,000 metric tons
- Main mining methods: underground, open pit, heap leaching
- Main silver-producing minerals: argentite, cerargyrite, stephanite
- Byproduct of: lead, zinc, copper, gold mining
- Main uses: coins/bullion, jewelry, electronics, silverware, photography
- Average crustal abundance: 0.07 parts per million
These key facts provide an overview of Earth’s silver supply and how it is extracted and utilized worldwide. Silver makes up only a tiny fraction of the Earth’s crust at 0.07 ppm, yet there are still over 500,000 metric tons of known reserves globally. The leading producers are concentrated in the Americas, and most mining is focused on silver-bearing lead, zinc, copper, and gold ores rather than primary silver minerals. While both underground and surface techniques are used, heap leaching has become an increasingly popular method. The majority of mined silver goes towards industrial applications and coins/bullion, with jewelry and silverware also utilizing substantial amounts.
Global Silver Reserves
According to the U.S. Geological Survey, the total estimated worldwide reserves of silver are approximately 530,000 metric tons. Reserves refer to deposits that have been discovered, evaluated, and determined to be economically feasible to mine under current conditions. Here are the top 10 countries with the largest known silver reserves:
| Country | Reserves (metric tons) |
|---|---|
| Peru | 120,000 |
| Poland | 85,000 |
| Chile | 77,000 |
| Australia | 44,000 |
| Russia | 35,000 |
| Mexico | 37,000 |
| China | 35,000 |
| United States | 25,000 |
| Bolivia | 22,000 |
| Argentina | 19,000 |
Peru holds the top spot with 24% of the world’s reserves at 120,000 metric tons. Poland comes in second at 85,000 metric tons (16%), followed by Chile with 77,000 (15%). Australia and Russia hold significant but smaller shares of global reserves. These top 5 countries possess 70% of total worldwide silver reserves.
Mexico, China, the United States, Bolivia, and Argentina round out the top 10, each holding 2-7% of total reserves. Taken together, the top 10 countries account for nearly 90% of global silver reserves. However, many other countries hold lesser but still substantial amounts, including Kazakhstan, Canada, Morocco, and South Africa.
Annual Worldwide Silver Production
In addition to reserves, another important metric is the total amount of silver produced globally each year from mining. According to statistics from The Silver Institute, in 2021 the total worldwide mine production of silver was 27,011 metric tons. Here are the top 10 silver-producing countries and their annual outputs:
| Country | Production (metric tons) |
|---|---|
| Mexico | 5,600 |
| Peru | 4,130 |
| China | 3,500 |
| Russia | 2,690 |
| Chile | 1,400 |
| Bolivia | 1,300 |
| Poland | 1,200 |
| Australia | 1,160 |
| United States | 980 |
| Argentina | 560 |
Mexico produces the most at 5,600 metric tons annually, accounting for 21% of global output. Peru, China, and Russia are also major producers. The top 7 countries generate over two-thirds of total worldwide mining production. Global silver output has risen substantially over the past two decades, more than doubling from 13,000 metric tons in 2000.
How Silver is Mined
There are several methods used to mine silver depending on the geology and location of the deposits. About 72% of silver is produced from ores, while the remaining 28% comes from recycling scrap and already-processed tailings and waste material.
Underground Mining
Underground mining is used when silver deposits are located deep below the Earth’s surface, sometimes as far down as 1 or 2 kilometers. Vertical shafts and horizontal tunnels are constructed to access the ore and haul it to the surface. Underground mining techniques include longwall mining, cut-and-fill stoping, shrinkage stope mining, and room-and-pillar mining. These methods are highly selective and can extract high-grade ore. However, they require significant infrastructure and have high operational costs compared to open pit mining.
Open Pit Mining
Also known as open cast mining, open pit is employed when silver deposits are located close to the surface. The overlying rock is dug up and moved aside using large excavators and dump trucks to expose the ore. Since it utilizes less expensive strip mining equipment rather than underground tunnels, open pit mining is more economically viable when dealing with large lower-grade ore bodies up to 500 meters deep. However, it generates significant environmental disturbance and waste rock.
Heap Leaching
An increasingly popular method, heap leaching is used to extract silver and other metals from very low-grade ores that are uneconomical to smelt directly. The crushed ore is piled on impermeable pads and irrigated with a chemical solution such as sodium cyanide or thiosulfate to dissolve the silver. The silver-bearing solution is then collected via drainage tunnels and processed to recover the metals. Heap leaching is cost-effective and environmentally safer than other mining methods.
Major Silver-Producing Minerals
While silver can be found alloyed with or in the atomic structure of many minerals, these are the primary silver-bearing ores that are mined:
- Argentite (Ag2S) – A silver sulfide, argentite contains 87.5% silver. The leading source, deposits often occur in veins. Common associated minerals are pyrargyrite and galena.
- Cerargyrite (AgCl) – Also known as horn silver, cerargyrite is a silver chloride mineral containing 75.2% silver. It forms in the oxidized zones above silver deposits.
- Stephanite (Ag5SbS4) – A silver antimonide sulfide, stephanite has 68.7% silver. It is often found in hydrothermal polymetallic veins along with pyrargyrite.
- Polybasite [(Ag,Cu)16Sb2S11] – A mixed silver-copper sulfosalt, polybasite contains a high silver content of 65-75%. Significant deposits are located in Idaho, USA and Coahuila, Mexico.
- Pyrargyrite (Ag3SbS3) – This antimony silver sulfosalt, also known as ruby silver, contains 59.9% silver. It forms red to black crystals in veins and replacements.
- Proustite (Ag3AsS3) – A light ruby-red silver arsenide sulfosalt, proustite contains 65.4% silver. It often occurs with acanthite and pyrargyrite.
- Acanthite (Ag2S) – Primarily composed of silver sulfide, acanthite is a soft, dark gray mineral with a silver content of 87.5%. It is found in many major silver deposits worldwide.
While not a major source, native silver in veins and as coatings on other minerals contains the highest silver concentration of any mineral at 100% Ag. Silver also substitutes for other metals in smaller amounts in common sulfides such as galena (PbS), sphalerite (ZnS), and chalcopyrite (CuFeS2).
Silver as a Byproduct
One of the unique attributes of silver mining is that very little comes from dedicated silver mines. Only around 30% of annual production comes from mines where silver is the primary economic metal. The remainder is mined as a byproduct of ores that are dominated by lead, zinc, copper, and gold. For example, lead-zinc deposits in Australia, Canada and Sweden yield significant silver, while polymetallic mines in South America extract silver along with tin, tungsten, and other metals.
This byproduct status can cause fluctuations in silver supply in response to economic conditions influencing base and precious metals demand rather than direct silver demand. However, the diversity of byproduct sources also limits major disruptions to global silver production. In many cases, silver recovered as a byproduct represents profitable additional income from already-economic deposits being mined for their primary metal content.
Main Uses of Silver
The majority of mined silver is utilized in the following key sectors:
Coins and Bullion
Silver coins and bullion bars represent the single largest application at around 28% of total demand. This investment and monetary role capitalizes on silver’s intrinsic value and established status as a precious metal. Government mints and private companies produce bullion products worldwide, with demand fluctuating based on market factors.
Jewelry
The brilliant white sheen and reflective qualities make silver a popular choice for jewelry at approximately 18% of demand. Sterling silver containing 92.5% Ag is the most common alloy for rings, bracelets, earrings, chains, and other jewelry. More expensive options include fine silver at 99.9% purity. Demand is largely driven by discretionary spending and fashion trends.
Industrial Applications
With its high electrical and thermal conductivity among the metals, silver is indispensable for electrical contacts and conductors, accounting for around 16% of total silver consumption. Electronics, automobiles, appliances, medical equipment, and other manufacturing sectors utilize silver components. Silver’s anti-microbial properties also drive industrial demand.
Silverware
The traditional use of silverware, cutlery, and serving trays constitutes around 12% of demand. Stainless steel has displaced silver for most applications, but sterling silver remains popular for upscale hotel chains and cruise lines. Plating base metals with silver through electroplating also continues.
Photography
While digital photography has reduced consumption, silver halide crystals in photographic film and paper still utilize around 9% of mine supply. Specialty black and white photography remains an important niche keeping demand stable. Some x-rays and other medical imaging still rely on silver.
Silver Recycling
Along with mining production, recycling helps boost annual silver supply by contributing around 28% of total output. Photographic film, jewelry, electronics, silverware, and scrap metal are all sources of recyclable silver. Processing tailings from existing mines also yields recoverable leftover silver. Recycling provides a more environmentally-friendly supplemental supply chain and offsets some demand for newly mined silver.
Silver Mining Companies
While many mining companies produce silver as a byproduct, these leading firms are primarily focused on silver production:
- Fresnillo Plc – Mexico-based company majority-owned by Industrias Penoles. World’s largest primary silver producer, operating seven mines in Mexico.
- KGHM Polska Miedź – Major Polish mining company that is the leading European silver producer with three mines in Poland.
- Polymetal International – Russian silver and gold producer with four major mines in Russia and Kazakhstan.
- Pan American Silver Corp. – Canadian company operating seven silver mines in Mexico, Peru, Bolivia, and Argentina.
- Compañía de Minas Buenaventura – Leading Peruvian precious metals mining company engaged in exploration, mining, and processing.
- Hecla Mining Company – Idaho-based firm operating silver, gold, lead, and zinc mines in the U.S., Canada, and Mexico.
- Coeur Mining Inc. – Chicago-based silver producer with five operating mines in the U.S., Mexico, and Australia.
- Hochschild Mining – Primarily Peru-focused company extracting silver and gold. Third largest silver producer globally.
- Southern Silver Exploration – Exploration and development company with silver assets in New Mexico, USA and Durango, Mexico.
- First Majestic Silver Corp. – Canadian mining company focused exclusively on silver production with six mines in Mexico.
These companies account for a substantial portion of worldwide silver mining output. Other diversified mining companies such as BHP Billiton, Glencore, and Teck Resources also produce significant byproduct silver.
Global Silver Exploration
While known global silver reserves and resources are substantial at around 2.5 million metric tons, exploration continues to search for new deposits and improve existing reserves.
Some major active exploration and development projects include:
- Navidad project – Located in Argentina, considered one of the largest undeveloped silver deposits with over 500 million ounces indicated.
- Corani project – Mainly silver-lead-zinc deposit under development in Peru with proven and probable reserves of 225 million ounces of silver.
- Pitarrilla Project – Large silver, lead, zinc deposit owned by SSR Mining in Durango State, Mexico. Estimated mineral resources of over 500 million ounces of silver.
- Salave Gold-Silver Project – Significant gold-silver deposit in Spain currently being explored and evaluated by Black Dragon Gold Corp.
- Juanicipio Project – Joint venture between MAG Silver and Fresnillo to develop a major epithermal silver-gold vein system in Zacatecas, Mexico.
- Cascabel project – Promising large copper-gold-silver project in Ecuador being explored by SolGold and BHP Billiton.
With improved exploration techniques and elevated silver prices stimulating investment, further major discoveries will add to global silver reserves over coming decades. However, average ore grades have declined across major silver producing countries as existing reserves are depleted. This will place more pressure on continued exploration to delineate higher grade resources.
Future Silver Supply and Demand
Both supply and demand for silver are expected to trend higher over the next decade according to projections from institutions such as The Silver Institute. However, supply may face constraints if prices drop significantly, as mining companies will focus on more profitable metals. Recycling contributions should continue to rise as private and industrial stocks of silver become available for recovery.
On the demand side, industrial applications and investment will remain strong drivers, supplemented by growth in jewelry, technology, and alternative energy applications such as solar panels if adoption accelerates. Supply shortages could potentially arise, which would drive prices and volatility higher. Overall, the market balance for silver is expected to remain relatively tight.
Increased use of silver nanomaterials and nanoparticles is an emerging area that could substantially impact demand. These ultra-small particles utilize silver’s anti-microbial properties in next-generation products. Electronics miniaturization may also support silver’s high technology utilization.
Conclusion
Silver has a long history of providing social and economic utility thanks to its unique characteristics and global abundance as a precious metal. While known reserves and resources of 530,000 metric tons are substantial, silver’s low crustal concentration and byproduct status make it challenging to predict production trends. As recycling and nanotechnology drive incremental demand, prices, mining technology, and exploration success will dictate whether mine supply can keep pace. But silver’s utility for industrial, monetary, and aesthetic applications shows no signs of abating.
