Chalcopyrite - CuFeS₂

Habit: Brass-yellow often massive, compact crystals, often with an iridescent tarnish. Opaque with a Metallic Luster.

Environment: Found in a wide variety of conditions. Primary mineral in Hydrothermal veins deposited at medium and high temperatures, disseminations and massive replacements. It is the primary minerals in several porphyry-copper deposits.

Etymology: From the Greek for brass and pyrite it is a widespread copper ore.