Stromeyerite
Image: <a href="//commons.wikimedia.org/wiki/User:Geolina163" title="User:Geolina163">Geolina163</a> (CC BY-SA 4.0)
Mineral NameStromeyerite
Chemical FormulaAgCuS
Mohs Hardness2.5
Crystal Systemorthorhombic
Lustermetallic
Streak Colorblackish-gray
Cleavageindistinct on {110}
Fractureconchoidal
Specific Gravity6.2
Colorsdark steel-gray, lead-gray, iridescent blue, purple, black
Transparencyopaque
Type LocalityFreiberg, Saxony, Germany
Mineral GroupSulfides
Usesminor ore of silver, minor ore of copper, collector's mineral
Associated Mineralschalcocite, bornite, native silver, acanthite, galena, sphalerite, pyrite, chalcopyrite
Rarityuncommon
Description
Stromeyerite is a dark steel-gray to lead-gray mineral, often tarnishing to iridescent blue or purple, typically found in massive or granular forms, sometimes as small orthorhombic crystals.
Geological Context
It is an uncommon hydrothermal mineral found in low-temperature copper-silver sulfide deposits, often associated with other sulfide minerals.
