Although zinc compounds have been used for at least 2,500 years in the production of brass, zinc wasn't recognized as a distinct element until much later.
Metallic zinc was first produced in India sometime in the 1400s by heating the mineral calamine (ZnCO3) with wool. Zinc was rediscovered by Andreas Sigismund Marggraf in 1746 by heating calamine with charcoal. Today, most zinc is produced through the electrolysis of aqueous zinc sulfate (ZnSO4).
Zinc is used to make many useful alloys. Brass, an alloy of zinc that contains between 55% and 95% copper, is probably the best known zinc alloy.
In 2011, U.S. production of recoverable zinc was 743,000 metric tons (t), a 3% increase from that of 2010. The value of domestic mine production was approximately $1.74 billion. Alaska continued to be the dominant zinc-producing State, followed by, in descending order of quantity, Tennessee, Missouri, and Idaho.
Domestic exports of zinc contained in ores and concentrates decreased by 12% to 660,000 t in 2011. Exports of zinc in concentrates were predominantly sent to the Republic of Korea (24%), Canada (23%), Spain (17%), and Japan (14%) (table 7). Imports for consumption of zinc contained in ores and concentrates decreased by 17% to 26,700 t from that in 2010.
Estimated U.S. refined zinc production in 2011 was essentially unchanged at 248,000 t. Imports of refined zinc in 2011 increased by 7% to 716,000 t.
Refined zinc was imported primarily from Canada (62%), Mexico (12%), Peru (9%), and Namibia (8%). Domestic exports of refined zinc increased by 14,800 t to 19,000 t in 2011. Globally, zinc mine production increased by 6% to 12.8 million metric tons (Mt); zinc metal production increased slightly to 13.1 Mt.
The value of zinc mined in 2012, based on zinc contained in concentrate, was about $1.53 billion. It was produced in 3 States at 13 mines operated by 4 companies. Two facilities—one primary and the other secondary—produced the bulk of refined zinc metal of commercial grade in 2012. Of the total zinc consumed, about 55% was used in galvanizing, 21% in zinc-based alloys, 16% in brass and bronze, and 8% in other uses.
Zinc compounds and dust were used principally by the agricultural, chemical, paint, and rubber industries. In 2012, about 57% (150,000 tons) of the slab zinc produced in the United States was recovered from secondary materials—mainly electric arc furnace dust, as well as galvanizing residues.
Import Sources (2008–11): Ore and concentrate: Peru, 81%; Canada, 7%; Ireland, 6%; Mexico, 6%. Metal: Canada, 74%; Mexico, 12%; Peru, 6%; Spain, 2%; and other, 6%. Waste and scrap: Canada, 63%; Mexico, 32%; Dominican Republic, 2%; Netherlands, 1%; and other, 2%. Combined total: Canada, 69%; Mexico, 12%; Peru, 10%; Spain, 2%; and other, 7%.
The meaning of "metal" differs for various communities. For example, astronomers use the blanket term "metal" for convenience to describe all elements other than hydrogen and helium (the main components of stars, which in turn comprise most of the visible matter in the universe) collectively. Thus, in astronomy and physical cosmology, the metallicity of an object is the proportion of its matter made up of chemical elements other than hydrogen and helium.[4] In addition, many elements and compounds that are not normally classified as metals become metallic under high pressures; these are known as metallic allotropes of non-metals.