Jalpaite
Jalpaite | |
---|---|
![]() Jalpaite crystals from Jalpa, Municipio de Jalpa, Zacatecas, Mexico (size: 3.6 x 3.5 x 3.2 cm) | |
General | |
Category | Sulfide mineral |
Formula (repeating unit) | Ag3CuS2 |
IMA symbol | Jal[1] |
Strunz classification | 2.BA.45 |
Crystal system | Tetragonal |
Crystal class | Ditetragonal dipyramidal (4/mmm) H-M symbol: (4/m 2/m 2/m) |
Space group | I41/amd |
Unit cell | a = 8.67, c = 11.75 [Å]; Z = 8 |
Identification | |
Color | Pale metallic gray |
Crystal habit | Irregular and foliated masses, inclusions in other minerals |
Cleavage | Prismatic, good |
Fracture | Subconchoidal |
Tenacity | Sectile, malleable |
Mohs scale hardness | 2 - 2.5 |
Luster | Metallic |
Streak | Black |
Diaphaneity | Opaque |
Specific gravity | 6.82–6.85 |
Pleochroism | Distinct in oil, brownish gray to pure gray |
Alters to | Tarnishes with iridescence |
References | [2][3][4] |
Jalpaite is a rare copper silver sulfide mineral with formula Ag3CuS2.
It was first described in 1858 for an occurrence in the Leonora Mine, Jalpa, Zacatecas, Mexico and named for the locality.[3] It occurs in low temperature hydrothermal veins at temperatures less than 117 °C (243 °F). Associated minerals include acanthite, mckinstryite, galena, sphalerite, pyrite, chalcopyrite, stromeyerite, polybasite, pearceite, tetrahedrite–tennantite and native silver.[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.
- ^ a b Handbook of Mineralogy
- ^ a b Mindat.org
- ^ Webmineral data