Sphalerite
Image: James St. John (CC BY 2.0)
Mineral NameSphalerite
Chemical Formula(Zn,Fe)S
Mohs Hardness3.5
Crystal Systemcubic
Lusterresinous
Streak Colorbrownish to yellow-brown
Cleavageperfect dodecahedral (6 directions)
Fractureconchoidal
Specific Gravity4
Colorsyellow, brown, black, red, green, colorless
Transparencytransparent
Type Localitymine near Carthage, Tennessee, USA
Mineral GroupSulfides
Useszinc ore, collector's specimens
Associated Mineralsgalena, pyrite, chalcopyrite, fluorite, calcite, dolomite, quartz
Raritycommon
Description
This specimen features dark, resinous to submetallic crystals, likely dark brown to black, exhibiting distinct crystal faces. The overall appearance is opaque and blocky.
Geological Context
Sphalerite commonly forms in hydrothermal veins, contact metamorphic deposits, and sedimentary exhalative deposits (SEDEX). It is often found in association with other sulfide minerals in these environments.
