| Andorite | |
|---|---|
Andorite - Itos Mine, Oruro City, Cercado Province, Bolivia. Specimen height is 4.1 cm. |
|
| General | |
| Category | Sulfosalt mineral |
| Chemical formula | PbAgSb3S6 |
| Strunz classification | 02.JB.40a |
| Crystal symmetry | Orthorhombic (2/m 2/m 2/m) dipyramidal |
| Unit cell | a = 12.99 Å, b = 19.14 Å, c = 4.3 Å; Z = 4 |
| Identification | |
| Color | Dark steel-gray, may tarnish yellow or iridescent; white in polished section |
| Crystal habit | Crystals stout prismatic to tabular on {100}, striations parallel to [001]; massive |
| Crystal system | orthorhombic |
| Twinning | On {110} |
| Cleavage | none observed |
| Fracture | conchoidal |
| Mohs scale hardness | 3 - 3.5 |
| Luster | metallic |
| Streak | Black |
| Diaphaneity | Opaque |
| Specific gravity | 5.33 - 5.37 |
| Optical properties | anisotropic |
| References | [1][2] |
Andorite is a sulfosalt mineral with the chemical formula PbAgSb3S6.
It was first described in 1892 for an occurrence in the Baia Sprie mine, Baia Sprie, Maramures County, Romania, and named for Hungarian amateur mineralogist Andor von Semsey (1833-1923).[1] [3] Andorite occurs in low-temperature polymetallic hydrothermal veins. It occurs associated with stibnite, sphalerite, baryte, fluorite, siderite, cassiterite, arsenopyrite, stannite, zinkenite, tetrahedrite, pyrite, alunite, quartz, pyrargyrite, stephanite and rhodochrosite.[2]