valleriite

{{infobox mineral | name = Valleriite | boxwidth = | boxbgcolor = | image = Cubanite-Maucherite-Valleriite-199922.jpg | imagesize = 260px | alt = | caption = Cubanite (brass yellow), maucherite (dark gray) and valleriite (dark bronze), mainly | category = Sulfide mineral | formula = | molweight = | strunz = 2.FD.30 | dana = 2.14.1.1 | system = Trigonal | class = Hexagonal scalenohedral (m) H-M symbol: ( 2/m) | symmetry = Rm | unit cell = a = 3.79, c = 34.1 [Å]; Z = 2 | color = Bronze-yellow, gray | colour = | habit = Massive, nodular, encrustations, thin splintery | twinning = | cleavage = Excellent on {0001} | fracture = | tenacity = | mohs = 1–1.5 | luster = Metallic | streak = Black | diaphaneity = Opaque | gravity = 3.14 (measured) | density = | polish = | opticalprop = | refractive = | birefringence = | pleochroism = Strong; pale yellow to deep brown | 2V = | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = | impurities = | alteration = | other = | references = }} Valleriite is an uncommon sulfide mineral (hydroxysulfide) of iron and copper with formula: or . It is an opaque, soft, bronze-yellow to brown mineral which occurs as nodules or encrustations.

==Discovery and occurrence== Valleriite was first described in 1870 from an occurrence in Västmanland, Sweden. It was named for Swedish chemist Johan Gottschalk Wallerius (Vallerius) (1709–1785).