Valleriite
Valleriite
Uncommon sulfide-hydroxide mineral of iron and copper
Valleriite is an uncommon sulfide mineral (hydroxysulfide) of iron and copper with formula: 4(Fe,Cu)S·3(Mg,Al)(OH)2[3] or (Fe2+,Cu)4(Mg,Al)3S4(OH,O)6.[2] It is an opaque, soft, bronze-yellow to brown mineral which occurs as nodules or encrustations.