Atheneite
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| Atheneite | |
|---|---|
| General | |
| Category | Arsenide mineral |
| Formula | (Pd,Hg)3As |
| IMA symbol | Ah[1] |
| Strunz classification | 2.AC.05a |
| Crystal system | Hexagonal |
| Crystal class | Ditrigonal dipyramidal (6m2) H-M symbol: (6m2) |
| Space group | P62m |
| Unit cell | a = 6.813, c = 3.4892 [Å]; Z = 3 |
| Identification | |
| Color | Gray to gray white; white with bluish tint in reflected light |
| Crystal habit | Irregular blebs, inclusions |
| Luster | Metallic |
| Diaphaneity | Opaque |
| Specific gravity | 10.2 |
| Pleochroism | Very weak, in pale yellow to pale bluish gray |
| References | [2][3][4] |
Atheneite is a rare palladium, mercury arsenide mineral with the chemical formula (Pd,Hg)3As associated with palladium–gold deposits. Its composition parallels that of arsenopalladinite (Pd8(As,Sb)3), isomertieite (Pd11Sb2As2) and meritieite-II (Pd8(Sb,As)3) (Cabral, 2002).
It was discovered in 1974 by A.M. Clark, A.J. Criddle, and E.E. Fejer in the Minas Gerais mine in the town of Itabira, Brazil (Clark, 1974). Atheneite was also found in 1982 during a major gold rush at Serra Pelada in northern Brazil. Since then it has been found in the northern region of Para, Brazil, the northern region of Russia, and the Limpopo province of South Africa (Cabral, 2002; Trabaev, 1995). Its name is derived from the Greek goddess Pallas Athena for its association with palladium-gold deposits. It was first found in concentrates from gold washings in Brazil with intergrowths of arsenopalladinite (Fleischer, 1974). Hematite was also found in intergrowths with atheneite, and is interpreted as being the product of a low temperature, hydrothermal origin.