Mineralpedia Details for Cornetite
Belgian geologist Jules Cornet is the namesake of the mineral Cornetite. It is a rare mineral that forms in some oxidized copper deposits in localities in the Democratic Republic of the Congo, Zambia, Zimbabwe, the United States, Chile, Mexico, and Australia among a few others. Mineral associated with Cornetite include copper, brochantite, pseudomalachite, libethenite, malachite, atacamite, chysocolla, and heterogenite.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/cornetite.pdf
Cornetite from Star of the Congo mine, Lubumbashi, Shaba, Congo
Dark blue, lustrous, flat radial aggregates to 4mm.
Cornetite from Yerington, Lyon Co., Nevada
Deep blue, lustrous very microcrystalline Cornetite. Crystals are less than 0.5mm.
Cornetite from Katanga Cu Crescent, Katanga, Democratic Republic of Congo
Deep blue compact crystals of Cornetite with dark green Malachite.