Cadmium

cadmium

greenockite

otavite

monteponite

Images

Formula: Cd
Native element
Specific gravity: 8.65
Hardness: 1 to 2
Colour: Tin-white with bluish tint
Melting point: 321.1^oC
Boiling point: 765^oC
Abundance in the Earth’s crust: 150 parts per billion by mass, 30 parts per billion by moles (ChC)
Abundance in the Solar System: 6 parts per billion by mass, 70 parts per trillion by moles (ChC)
Environments

Plutonic igneous environments
Sedimentary environments

Cadmium ocurs rarely in the native state, most often in small quantities associated with zinc ores, such as sphalerite. Greenockite is the only cadmium mineral of any consequence. Almost all cadmium is obtained as a by-product of zinc, copper and lead ore refining operations (ChC).

Localities

At the type locality, the Ust'-Khann'ya Intrusion, Lower Khann'ya River, Vilyui River Basin, Mirninsky District, Sakha Republic, Russia, Native cadmium was reported as microscopic grains in the heavy, non-magnetic fraction of a concentrate from gabbro-dolerite. Associated minerals reportedly include moissanite, iron, copper, lead, tin, zinc, copper–zinc alloy, tin–antimony alloy, sulphides, garnet, spinel, kyanite, corundum and rutile (the assemblage seems highly improbable) (AM 65.1065, HOM).

At the Yana River Basin, Verkhoyansk District, Sakha Republic, Russia, cadmium is a product of post-magmatic activity in mineralised siltstone, sandstone, dolostone and mudstone. Associated minerals include monteponite, otavite, titanite, ilmenite, chalcopyrite, bornite, chalcocite, pyrite and galena (HOM).

Cadmium-bearing minerals include:

Sulphides - the sulphide anion is S^2-
Selenides - the selenide anion is Se^2-
Sulphosalt - A_mB_nX_p: where A is a metal , B usually a semi-metal and X is sulphur, selenium or tellurium
Oxides - the oxide anion is O^2-
Carbonates - the carbonate anion is (CO₃)^2-
Sulphates - the sulphate anion is (SO₄)^2-
Selenites - the selenite anion is (Se⁴⁺O₃)^2-
Arsenates - the arsenate anion is (As⁵⁺O₄)^3-

Back to Minerals