clausthalite

{{Infobox mineral | name = Clausthalite | category = Selenide mineral | boxwidth = | image = Clausthalite-207330.jpg | alt = | caption = | formula = PbSe | IMAsymbol = Cth | molweight = | strunz = 2.CD.10 | dana = 02.08.01.02 | system = Isometric | class = Hexoctahedral (mm) H-M symbol: (4/m 2/m) | symmetry = Fmm | color = Bluish gray to lead-gray | colour = | habit = Massive to granular with euhedral crystals | twinning = | cleavage = {001} Perfect, {010} Perfect, {100} Perfect | fracture = | tenacity = | mohs = 2.5 | luster = Metallic | streak = grayish black | diaphaneity = opaque | gravity = 7.6–8.8 | density = | polish = | opticalprop = | refractive = | birefringence = | pleochroism = | 2V = | dispersion = | extinction = | length fast/slow = | fluorescence= | absorption = | melt = | fusibility = | diagnostic = | solubility = | other = | alteration = | references = }} Clausthalite is a lead selenide mineral, PbSe. It forms a solid solution series with galena PbS.

==Occurrence== It occurs in low-sulfur hydrothermal deposits with other selenides and in mercury deposits. It is associated with tiemannite, klockmannite, berzelianite, umangite, gold, stibiopalladinite and uraninite.