Gold and Silver

Gold

• Gold is a chemical element with the symbol Au (from the Latin word "aurum") and atomic number
79.
• It is a dense, soft, malleable, and ductile metal with a bright yellow colour, known for its lustrous
appearance and high value.
• Gold in its purest form is dense, soft malleable and ductile metal.
• It is one of the least reactive chemical elements (resistant to corrosion).
• Gold often occurs in free elemental (native) form, as nuggets or grains, in auriferous (rocks
containing gold) rocks, in vein, and in alluvial deposits.
• As an excellent conductor of heat and electricity, gold finds diverse applications across industries
such as jewellery, electronics, dentistry, investment, aerospace, and medicine.

Geological Formation of Gold

• Gold deposits form through various geological processes and occur in diverse geological
settings.
• Hydrothermal vein deposits, formed by hot fluids migrating through fractures, are among the
most common sources of gold, often associated with volcanic and tectonic environments.
• Placer deposits, created through erosion and weathering of primary deposits, accumulate in
sedimentary environments like riverbeds and beach sands.
• Carlin-type deposits, characterized by their association with carbonate rocks, are found in
sedimentary basins with thick sequences of carbonate rocks.
• Epithermal deposits, formed by cooler hydrothermal fluids at shallow depths, are common in
volcanic and geothermal environments.
• Greenstone-hosted deposits occur in association with volcanic and sedimentary rocks known
as greenstones, found in tectonically active regions.

Gold Reserves and Production in India

• As of 2015, the total reserves of gold ore in the country have been estimated at 501.8 MT.
• As of April 1, 2020, India's total reserves and resources of gold comprise 518,234,370.2 tonnes
of primary ore and 607.26 tonnes of primary metal. Additionally, there are 26,121,000 tonnes
of placer ore and 5.86 tonnes of placer metal.
• In the fiscal year 2021-22, primary gold production reached 1,251 kilograms, reflecting a
growth of approximately 10.99% compared to the preceding year.
• Karnataka emerged as the dominant contributor, accounting for 99.07% of the total
production, with Jharkhand contributing the remainder.
India’s Gold Ore reserves India’s Gold Production
State % Share In terms of Metal State FY 2021-22
Content
1. Bihar 44% 1. Karnataka 1. Karnataka 99%
2. Rajasthan 25% 2. Rajasthan 2. Jharkhand 1%
3. Karnataka 21% 3. Andhra Pradesh The domestic production nowhere
4. West Bengal 3% 4. Bihar meets the domestic demand. The
5. Andhra 3% 5. Jharkhand demand is mainly met through
Pradesh imports.
6. Jharkhand 2% Total: 655 Tons Total 1,250 kg
Karnataka • Gold mines are located in Kolar (Kolar Gold Field), Dharwad, Hassan and
Raichur (Hutti Gold Field) districts.
• Kolar Gold Fields is one of the deepest mines of the world. (Usually, gold
mines are the deepest mines in the world. Mponeng Gold Mine in South
Africa is one of the deepest mine in the world (3.9 km deep)).
• Hutti mines are exploited to their maximum levels and the ore left behind
is of very low grade.
• The Kolar Gold Field has also run out of quality reserves and is on the
verge of closure.
Jharkhand • Sands of the Subarnarekha (gold streak) river have some alluvial gold.
• Sona nadi in Singhbhum district is important.
• Sonapat valley is another major site with alluvial gold.
Andhra Pradesh • Ramagiri in Anantapur district is the most important gold field in AP
Kerala • The river terraces along the Punna Puzha and the Chabiyar Puzha have
some alluvial gold.
World’s Gold Reserves and Gold Production
World’s Gold Reserves (in World’s Production of Gold in
TT) 2019 (tonnes)
Country Reserves Country Production Major gold mines
 1. Australia 10 1. China 380 11.3% • The Muruntau mine, Uzbekistan is
2. Russia 7.5 2. Australia 326 9.7% one of the largest gold mines in the
3. South Africa 2.7 3. Russia 305 9.09% world.
4. USA 3 4. USA 200 5.97% • Kalgoorlie Superpit Gold Mine,
5. Indonesia 2.6 5. Canada 183 5.46% Western Australia.
World Total 54 TT World Total 3.3 TT • Boddington Gold Mine, Western
Australia.
• Grasberg mine, Indonesia.

• Globally, gold production totalled approximately 3,350 metric tons in 2019.

 Source: World Gold Council

Silver

• Silver is grouped in the category of noble metals (highly resistant to corrosion; e.g. gold,
platinum, etc.).
• Silver is known to have the highest electrical and thermal conductivity amongst all metals.
• The chief ore minerals of silver are stephanite, pyrargyrite and proustite.
• Silver, characterized by its softness, lustrous appearance, and classification as a noble metal,
boasts a brilliant white colour and exceptional malleability, making it highly sought after for a
 multitude of industrial applications. Its resistance to atmospheric oxidation further enhances its
value as a precious metal.
• Silver's high electrical conductivity makes it indispensable in modern technology for printed
circuits, electronic coatings, and electrical contacts.
• Its light-sensitive compounds are crucial in photography, and its paste form is vital in solar cells,
driving demand in the photovoltaic market.

Geological Formation of Silver

• Primary deposits, which are the main sources of silver, are typically found in hydrothermal veins,
where hot, mineral-rich fluids seep through fractures in rocks, leaving behind deposits of silver
along with other valuable minerals such as lead, zinc, and gold.
• Famous examples include Nevada’s Comstock Lode and Mexico’s Guanajuato district.
• Skarn deposits, occurring at the contact zones between limestone and intrusive igneous rocks,
are also significant sources of silver. For example, China’s Daye mine and Mexico’s Cananea mine.
• Secondary deposits of silver are formed through the weathering and erosion of primary
deposits, with silver particles transported and deposited in sedimentary basins.

Silver Reserves and Production – India & World

• In India, there are no native silver deposits except the small Bharak deposit in Rajasthan.
• Silver occurs generally with lead, zinc, copper (especially their sulphide ore) and gold ores and is
extracted as a by-product from electrolysis or chemical methods.
• Silver was recovered in the past as a co-product in gold refining at KGF and Hutti Gold Mines
in Karnataka.
• Silver is now recovered as a by-product from Hindustan Zinc Smelter, Chanderiya, Chittorgarh
in Rajasthan, Tundoo smelter in Jharkhand and Visakhapatnam smelter in AP and from gold
refinery of Hutti.
• The Hindustan Copper Ltd. at Maubhandar smelter in Singhbhum district of Jhakhand obtains
silver from copper slimes.
• India's total reserves and resources of silver ore as of 2015, were estimated at approximately
511.95 million tonnes.
• Rajasthan held the majority share of reserves and resources accounts for 87% reserves in terms
of ore, Jharkhand 5%, Andhra Pradesh 3% and Karnataka 2%.
• In the fiscal year 2021-22, the production of silver amounted to 647,140 kilograms.
• Rajasthan is the leading producer with approximately 80% of production followed by Karnataka
(8%).
• In 2022, global silver imports totalled 10,600 tonnes, equivalent to 1.06 million tonnes, as
reported by the World Silver Survey 2023.
• Peru constituted the largest share of imports, accounting for 24% of the total. The United Arab
Emirates represented 22% of silver imports and Singapore contributed 19%. Switzerland
accounted for 16% of the total imports, with Bolivia making up the remaining 13%.
World’s Silver Reserves World’s Production of Silver
(in MT) in 2022 (in MT)
Country Reserves Country Production
1. Mexico 266 1. Mexico 1.36
2. Chile 213 2. China 1.08
3. Peru 172 3. Peru 1.01
World Total 1,380 World 6.8 MT