Wiktionary
jalpaite
n. (context mineralogy English) A tetragonal-ditetragonal dipyramidal mineral containing copper, silver, and sulfur.
Wikipedia
Jalpaite
Jalpaite is a rare copper silver sulfide mineral with formula AgCuS.
It was first described in 1858 for an occurrence in the Leonora Mine, Jalpa, Zacatecas, Mexico and named for the locality. 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.