Bornite
Bornite is a striking metallic ore that can display a rainbow of metallic colours. Formula: Cu5FeS4 Colour: Copper-red to pinchbeck-brown, quickly tarnishing to an iridescent purplish blue surface. Lustre: Metallic Hardness: 3 Specific Gravity: 5.06 – 5.09 Crystal System: Orthorhombic
