Cobaltite
Formula: CoAsS
Species: Sulfides
Colour: Reddish silver white, violet steel gray, or black.
Lustre: Metallic
Hardness: 5½
Specific Gravity: 6.33
Crystal System: Orthorhombic
Member of: Cobaltite Group. Cobaltite-Gersdorffite Series.
Name: From the German, Kobold, “underground spirit” or “goblin,” in allusion to the refusal of cobaltiferous ores to smelt properly, hence “bewitched.”