Jalpaite | |
Category: | Sulfide mineral |
Formula: | Ag3CuS2 |
Imasymbol: | Jal[1] |
Strunz: | 2.BA.45 |
System: | Tetragonal |
Class: | Ditetragonal dipyramidal (4/mmm) H-M symbol: (4/m 2/m 2/m) |
Symmetry: | I41/amd |
Unit Cell: | a = 8.67, c = 11.75 [Å]; Z = 8 |
Color: | Pale metallic gray |
Habit: | Irregular and foliated masses, inclusions in other minerals |
Cleavage: | Prismatic, good |
Fracture: | Subconchoidal |
Tenacity: | Sectile, malleable |
Mohs: | 2 - 2.5 |
Luster: | Metallic |
Streak: | Black |
Diaphaneity: | Opaque |
Gravity: | 6.82–6.85 |
Pleochroism: | Distinct in oil, brownish gray to pure gray |
Alteration: | 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 . Associated minerals include acanthite, mckinstryite, galena, sphalerite, pyrite, chalcopyrite, stromeyerite, polybasite, pearceite, tetrahedrite–tennantite and native silver.[2]