| Hutchinsonite | |
|---|---|
 Hutchinsonite, from Quiruvilca Mine, Santiago de Chuco Province, Peru. Size: 4.5×4.4×2.2 cm | |
| General | |
| Category | Sulfosalt mineral |
| Formula (repeating unit) | (Tl,Pb)2As5S9 |
| IMA symbol | Hut[1] |
| Strunz classification | 2.HD.45 |
| Crystal system | Orthorhombic |
| Crystal class | Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m) |
| Space group | Pbca |
| Identification | |
| Color | Red, pink, black |
| Crystal habit | Acicular – cccurs as needle-like crystals |
| Cleavage | {100} good |
| Fracture | Very brittle fracture producing small, conchoidal fragments |
| Mohs scale hardness | 1.5–2 |
| Luster | Sub-metallic |
| Streak | Red |
| Diaphaneity | Subtranslucent to opaque |
| Specific gravity | 4.6 |
| Optical properties | Biaxial (−) |
| Refractive index | nα = 3.078 nβ = 3.176 nγ = 3.188; 2V = 37° |
| Birefringence | δ = 0.110 |
| References | [2][3][4] |
Hutchinsonite is a sulfosalt mineral of thallium, arsenic and lead with formula (Tl,Pb)2As5S9. Hutchinsonite is a rare hydrothermal mineral.
It was first discovered in a sample from Binnental, Switzerland in 1903 and named after Cambridge mineralogist Arthur Hutchinson, F.R.S. (1866–1937) in 1904.
