Sphalerite, Colusite
ZnS,
Cu13VAs3S16
Locality:
Fossa degli Angeli quarry, Torano quarrying basin, Carrara, Massa-Carrara Province, Tuscany, Italy
Largest Crystal Size: 1.5 mm
Golden yellow sphalerite crystal with colusite and enargite in epitactic growth.
Italo Campostrini’s Photo
Sphalerite is named after Greek word for “mistaken”, because the mineral was often mistaken for galena, but contained no lead. Sphalerite forms clear crystals with colours ranging from pale yellow to orange and red shades, with the presence of iron it forms dark, opaque metallic crystals. Gem-quality material often has yellowish to honey brown, red to orange, or green colour. The brilliant cut best displays sphalerite’s high dispersion of 0.156 (three times as high as for diamond). Because of its softness and fragility sphalerite gems are usually used as collector’s pieces and sometomes set into pendants.
