Delafossite
Delafossite is a copper iron oxide mineral with formula CuFeO2 or CuFeO2. It is member of the delafossite mineral group with a general formula ABO2, a group characterized by a sheet of linearly coordinated A cations stacked between edge-shared octahedral layers (BO6). Delafossite along with other minerals of the ABO2 group has been recognized for its electrical properties from insulation to metallic conduction. Delafossite is usually a secondary mineral that crystallizes near oxidized copper and is rarely a primary mineral.