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Arsenate minerals usually refer to the naturally occurring orthoarsenates, possessing the (AsO 4) 3− anion group and, more rarely, other arsenates with anions like AsO 3 (OH) 2− (also written HAsO 4 2−) (example: pharmacolite Ca(AsO 3 OH). 2H 2 O) or (very rarely) [AsO 2 (OH) 2] − (example: andyrobertsite). Arsenite minerals are much ...
Transition metal arsenate compounds are often brightly coloured and have been used to make pigments. Copper arsenate was a minor compound used in the Egyptian blue pigment used by the ancient Egyptians and Romans. [10] Cobalt violet pigment was made from cobalt arsenate before its toxicity led to its replacement by cobalt phosphate. [11] [12] [13]
Scorodite is a common hydrated iron arsenate mineral, with the chemical formula FeAsO 4 ·2H 2 O. It is found in hydrothermal deposits and as a secondary mineral in gossans worldwide. Scorodite weathers to limonite. Scorodite was discovered in Schwarzenberg, Saxony, Germany. Named from the Greek Scorodion, "garlicky". When heated it smells of ...
Arsenate minerals are those minerals containing the arsenate (AsO 4 3−) anion group. Both the Dana [1] and the Strunz [2] mineral classifications place the arsenates in with the phosphate minerals .
Synthetic arsenates include Scheele's Green (cupric hydrogen arsenate, acidic copper arsenate), calcium arsenate, and lead hydrogen arsenate. These three have been used as agricultural insecticides and poisons. The protonation steps between the arsenate and arsenic acid are similar to those between phosphate and phosphoric acid.
Mixite is a rare copper bismuth arsenate mineral with formula: BiCu 6 (AsO 4) 3 (OH) 6 ·3(H 2 O). It crystallizes in the hexagonal crystal system typically occurring as radiating acicular prisms and massive encrustations.
Arthurite is a mineral composed of divalent copper and iron ions in combination with trivalent arsenate, phosphate and sulfate ions with hydrogen and oxygen. [2] Initially discovered by Sir Arthur Russell in 1954 at Hingston Down Consols mine in Calstock, Cornwall, England, [3] arthurite is formed as a resultant mineral in the oxidation region of some copper deposits by the variation of ...
Mimetite is a lead chloride arsenate mineral with the composition Pb 5 (AsO 4) 3 Cl. It is a secondary mineral, formed by oxidation of primary lead minerals in arsenic-bearing lead deposits. [ 2 ] It typically forms short hexagonal crystals that are yellow to brown to orange in color, very brittle, moderately hard ( Mohs hardness 3.5–4), and ...