cobaltite

{{Infobox mineral | name = Cobaltite | category = Sulfide mineral | boxwidth = | boxbgcolor = | image = Koboltglans.jpg | imagesize = | caption = Cobaltite from Sweden | formula = CoAsS | IMAsymbol=Cbt | molweight = | strunz = 2.EB.25 | system = Orthorhombic | class = Pyramidal (mm2) (same H-M symbol) | symmetry = Pc21b | unit cell = a = 5.582 Å, b = 5.582 Å, c = 5.582 Å; Z = 4 | color = Reddish silver white, violet steel gray to black | habit = Granular to massive, rarely as striated crystals, pseudocubic. | twinning = About [111] creating pseudo-cubic forms and striations | cleavage = Perfect on {001} | fracture = Uneven | tenacity = Brittle | mohs = 5.5 | luster = Metallic | refractive = | opticalprop = | birefringence = | pleochroism = | streak = Grayish-black | gravity = | density = 6.33 g/cm3 | melt = | fusibility = | diagnostic = | solubility = | diaphaneity = Opaque | other = | references = }} Cobaltite is an arsenide and sulfide mineral with the mineral formula CoAsS. It is the naming mineral of the cobaltite group of minerals, whose members structurally resemble pyrite (FeS2).

== History == Cobaltite was first described in 1797 by Klaproth. Its name stems from the contained element cobalt, whose name is attributed to the German term Kobold, referring to an "underground spirit" or "goblin". The notion of "bewitched" minerals stems from cobaltite and other cobalt ores withstanding the smelting methods of the medieval period, often producing foul-smelling, poisonous fumes in the process.