Cadmium 

Statistics and Information:  Cadmium, a soft, malleable, ductile, bluish-white metal, was discovered in Germany in 1817, and Germany remained the only important producer for 100 years. Currently, a large percentage of global cadmium metal production takes place in Asia.

Cadmium is generally recovered as a byproduct from zinc concentrates. Zinc-to-cadmium ratios in typical zinc ores range from 200:1 to 400:1. Sphalerite (ZnS), the most economically significant zinc mineral, commonly contains minor amounts of other elements; cadmium, which shares certain similar chemical properties with zinc, will often substitute for zinc in the sphalerite crystal lattice. The cadmium mineral, greenockite (CdS), is frequently associated with weathered sphalerites and wurtzites [(Zn, Fe)S], but usually at microscopic levels. A significant amount of cadmium is also recovered from spent nickel cadmium batteries.

Cadmium is primarily consumed for the production of rechargeable nickel cadmium batteries; other end uses include pigments, coatings and plating, and as stabilizers for plastics. Solar cell manufacturing may become another significant market for cadmium in the future. Cadmium telluride thin-film photovoltaics are an alternative to the traditional silicon-based solar cells and are a preferred photovoltaic technology for commercial rooftop applications and for large-scale, ground-mounted utility systems.

Cadmium
(Data in metric tons of cadmium content unless otherwise noted)

Domestic Production and Use: Two companies in the United States produced cadmium metal in 2007. One company, operating in Tennessee, recovered cadmium as a byproduct of zinc leaching from roasted sulfide concentrates. The other company, located in Pennsylvania, thermally recovered cadmium metal from spent nickel-cadmium (NiCd) batteries and other cadmium-bearing scrap. A third company located in Illinois, which historically recovered byproduct cadmium from zinc concentrates, shuttered in 2006 owing to recent mine closures and the increasing cash price of zinc concentrate. As a result of the closure, U.S. refinery production in 2007 was withheld in order to protect the company proprietary data of the remaining two operations. Based on the average New York dealer price, U.S. cadmium metal consumption was valued at about $3.62 million in 2007. Cadmium use in batteries amounted to an estimated 83% of apparent consumption. The remaining 17% was distributed as follows: pigments, 8%; coatings and plating, 7%; stabilizers for plastics, 1.2%; and nonferrous alloys, photovoltaic device