Jalpaite Locality: Jalpa , Municipio de Jalpa, Zacatecas , Mexico ( Locality at mindat.org ) Size: miniature, 3.6 x 3.5 x 3.2 cm Jalpaite Jalpaite is a very rare species, and only a few large crystals are known to exist. This specimen, believed to have been found around the turn of the 1900s, is huge for the species. And, it is quite attractive. This crystal is pronounced to be the best of species, by those who have studied Mexican mineralogy far more than I. It comes from the type locality, and was passed down through several hands to Dr. Romero for his collection. This specimen from the Dr Miguel Romero collection was on loan exhibition to the University of Arizona Museum for over a decade, until my purchase of this collection in 2008. It was on display in special cases at the museum, and has since been featured in the book "The Miguel Romero Collection of Mexico Minerals" which we sponsored as a special supplement book (published by the Mineralogical Record in December of 2008). — Photo: Robert M. Lavinsky · CC BY-SA 3.0
Jalpaite
A rare silver-copper sulfide described in 1858 from the Leonora mine at Jalpa, Mexico.
Intro adapted from Wikipedia (CC BY-SA).
Jalpaite is an IMA-recognized mineral species in the sulfide class, with the chemical formula Ag₃CuS₂.
It crystallizes in the tetragonal crystal system (space group I4_1/amd). It is a member of the Jalpaite structural group.
Key properties: Mohs hardness 2–2.5; specific gravity 6.82–6.85; Black streak; Metallic luster.
IMA symbol Jal, grandfathered status — known before the IMA’s founding, named in 1858.
Formed under low-temperature (below 117 ° C) hydrothermal conditions.
It is found associated with Acanthite, mckinstryite, galena, sphalerite, pyrite, chalcopyrite, stromeyerite, polybasite, pearceite, tetrahedrite–tennantite, silver.
The name refers to the Mexican locality at Jalpa.