Smithite is a sulfosalt mineral with the chemical formula AgAsS2. It was first described by mineralogist R H Solly in 1905, in samples from the Lengenbach quarry near Binn, Switzerland, and was named for Herbert Smith, who was an assistant in the department of mineralogy of the British Museum (Natural History).[3] Smithite is a dimorph of trechmannite.
| Smithite | |
|---|---|
 Red smithite with imhofite | |
| General | |
| Category | sulfosalt mineral |
| Formula (repeating unit) | AgAsS2 |
| IMA symbol | Sth[1] |
| Strunz classification | 2.GC.30 |
| Crystal system | Monoclinic |
| Identification | |
| Formula mass | 246.92 g/mol |
| Color | Pale red (changes to orange on exposure to light) |
| Crystal habit | hexagonal pyramid |
| Cleavage | Perfect, parallel to (100) |
| Mohs scale hardness | 1.5 – 2 |
| Luster | Adamantine |
| Streak | vermilion |
| Specific gravity | 4.88 |
| References | [2] |
References
edit- ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
- ^ "Smithite". mindat.org. Retrieved 2024-10-27.
- ^ Solly, RH (1905). "Some new minerals from the Binnenthal, Switzerland" (PDF). Mineralogical Magazine. 14: 72–82. doi:10.1180/minmag.1905.014.64.03.
Wikimedia Commons has media related to Smithite.