Sperrylite
| Sperrylite | |
|---|---|
| General | |
| Category | Arsenide mineral Pyrite group |
| Formula | PtAs2 |
| IMA symbol | Spy |
| Strunz classification | 2.EB.05a |
| Crystal system | Isometric |
| Crystal class | Diploidal (m3) H-M symbol: (2/m 3) |
| Space group | Pa3 |
| Unit cell | a = 5.967 Å, Z = 4 |
| Identification | |
| Color | Tin white |
| Crystal habit | Well-formed finely crystalline, massive to reniform |
| Cleavage | Indistinct on {001} |
| Fracture | Conchoidal |
| Tenacity | Brittle |
| Mohs scale hardness | 6–7 |
| Luster | Metallic |
| Streak | Black |
| Specific gravity | 10.58 |
| References | |
Sperrylite is a platinum arsenide mineral with the chemical formula PtAs2 and is an opaque metallic tin white mineral which crystallizes in the isometric system with the pyrite group structure. It forms cubic, octahedral or pyritohedral crystals in addition to massive and reniform habits. It has a Mohs hardness of 6–7 and a very high specific gravity of 10.6.
It was discovered by the American chemist Francis Louis Sperry in 1888-89 in ore from the Vermillion Mine, part of the Sudbury Basin discoveries, as he did a fire assay to determine the gold content of the ore for the Canadian Copper Company who were interested by the property.
The most important occurrence of sperrylite is in the nickel ore deposit of Sudbury Basin in Ontario, Canada. It also occurs in the layered igneous complex of the Bushveld region of South Africa and the Oktyabr'skoye copper-nickel deposit near Noril'sk, Russia.