Nonenergy minerals include base and precious metals, industrial metals, and gemstones, among others. Gold, copper, iron, and zinc are the principal contributors to metal mine production.
Gold can be found in both loose materials and hard rocks. Miners extract gold from placer mines using sluicing, dredging, jigging, and amalgamation devices that separate the gold from water, silt, rock, and other compounds. Lode mining, both open pit and underground, extracts gold embedded within rock walls. Once mined, gold is used to make jewelry, electronics, dental treatments, and other products.
In the United States, recent exploration for gold resulted in discoveries along the Carlin and Battle Mountain-Eureka (Cortez) trends in Eureka and Elko Counties. Read more about gold from the U.S. Geological Survey (USGS).
Copper is found in hard rocks in the form of copper ore. Miners extract copper from open pit and underground mines through traditional quarrying to separate the copper from rock, or leaching which involves treating the ore with diluted sulfuric acid. Once produced, copper has a variety of uses, including as a building material, as an effective conductor of electricity, and within the health care sector.
Iron is found in underground rocks. Miners extract iron by drilling holes in the ground in carefully engineered patterns and blasting out rocks with explosives. Next, miners crush the rocks and separate out the iron ore from other materials. Almost all iron is used to make steel, which in turn is used to make buildings, infrastructure, machines, and vehicles.
Lead is a corrosion-resistant, dense, ductile, and malleable metal. Environmental and health concerns have reduced or eliminated the use of lead in almost all non-battery products. Today, batteries account for more than 85% of lead consumption. Read more about lead from USGS.
Sphalerite or zinc oxide is the principal ore mineral in the world. Zinc is found in many items including metal products, rubber, and medicines. 75% of zinc goes into metal products to protect iron and steel from corrosion, but also to make bronze and brass. The other 25% is used by the rubber, chemical, paint, and agricultural industries. Read more about zinc from USGS.
Silver is a metal that has been used for thousands of years. It has the highest thermal and electrical conductivity, and is the whitest color of all metals. This makes it useful in the production of mirrors, electrical and electronic products, and photography. Its estimated domestic uses today are 30% electrical and electronics, 27% coins and medals, 7% jewelry and silverware, 6% photography, and 30% other. Predominantly recovered as a byproduct, the amount of silver still in existence is unknown. Read more about silver from USGS.
Molybdenum is extraordinarily resistant to heat and wear. It is typically used as a mixing agent in steel, cast iron, and superalloys to enhance hardenability, strength, toughness, and corrosion resistance. It plays a versatile and significant role in industrial technology and is also used in chemical applications such as catalysts, lubricants, and pigments. Read more about molybdenum from USGS.