| Petzite | |
|---|---|
Petzite with quartz - Sacarîmb, Nagyág, Romania |
|
| General | |
| Category | telluride mineral |
| Chemical formula | Ag3AuTe2 |
| Strunz classification | 02.BA.40a |
| Identification | |
| Color | Steel-gray to iron-black, commonly tarnished from bronze-yellow to sooty black; grayish white with a pale bluish tint in polished section |
| Crystal habit | Granular to massive |
| Crystal system | Cubic Gyroidal H-M Symbol (4 3 2) |
| Fracture | Subconchoidal irregular |
| Tenacity | Slightly sectile to brittle. |
| Mohs scale hardness | 2.5 - 3 |
| Luster | Metallic |
| Streak | Grayish black |
| Diaphaneity | Opaque |
| Specific gravity | 8.7 - 9.14 |
| References | [1][2][3] |
The mineral petzite, Ag3AuTe2, is a soft, steel-gray telluride mineral generally deposited by hydrothermal activity. It forms isometric crystals, and is usually associated with rare tellurium and gold minerals, often with silver, mercury, and copper.
The name comes from chemist W. Petz, who first analyzed the mineral from the type locality in Săcărâmb, Transylvania, Romania in 1845.[1][2]
It occurs with other tellurides in vein gold deposits. It is commonly associated with native gold, hessite, sylvanite, krennerite, calaverite, altaite, montbrayite, melonite, frohbergite, tetradymite, rickardite, vulcanite and pyrite.[1]