Chemistry

Ankerite is a calcium, iron, magnesium, manganese carbonate mineral of the group of rhombohedral carbonates with the formula: Ca(Fe, Mg, Mn)(CO3)2. It forms in iron-rich hydrothermal…

Anhydrite is a mineral – anhydrous calcium sulfate, CaSO4. It is not a common mineral, as it easily alters the much more common mineral Gypsum…

Anglesite is a lead sulfate mineral with the chemical formula PbSO4. It is a secondary lead mineral that always forms through the alteration of lead…

Andyrobertsite is a rare, complex arsenate mineral with a blue color. It is found in the Tsumeb mine in Namibia and named after Andrew C.…

Andradite is a species of the garnet group. It is a nesosilicate, with formula Ca3Fe2Si3O12. It is a member of the Garnet group, and although…

Andesine is a silicate mineral, a member of the plagioclase feldspar solid solution series. Its chemical formula is (Ca, Na)(Al, Si)4O8, where Ca/(Ca + Na)…

Andersonite, Na2Ca (UO2) (CO3)3·6H2O, or hydrated sodium calcium uranyl carbonate. It is a rare uranyl carbonate mineral, that was only described in the last half…

Andalusite is an aluminum nesosilicate mineral with the chemical formula Al2SiO5. It is a polymorph with two other minerals: kyanite and sillimanite. Andalusite is trimorphic…

Anatase is one of the three mineral forms of titanium dioxide (TiO2), the other two being brookite and rutile. At higher temperatures, about 915 degrees…

Ancylite is a group of hydrous strontium carbonates minerals containing cerium, lanthanum and minor amounts of other rare-earth elements. The composition is Sr(Ce, La)(CO3)2(OH)·H2O with…

Anapaite is a calcium–iron phosphate mineral with formula: Ca2Fe2+ (PO4)2·4H2O. It is rare and beautiful phosphate mineral. It is a mineral that typically occurs in…

Anandite is a rare phyllosilicate with formula (Ba, K)(Fe2+, Mg)3(Si, Al, Fe)4O10(S, OH)2. It crystallizes in the monoclinic crystal system. It is black in color with…