Mineralpedia Details for Ceruleite
Named for the Latin word caeruleus, meaning “sky blue,” in reference to the mineral’s common color. Ceruleite is a rare mineral that occurs in Chile at a couple localities, Bolivia, England at several localities, France at the Cap Garonne mine in Var, Australia at Bali Lo at the Ashburton Downs in Western Australia, and Namibia, among only a couple others. It can be found in oxidized arsenic-rich polymetallic deposits and as a post mine product.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/ceruleite.pdf
Ceruleite from Wheal Gorland, St. Day dist., Cornwall, England
Tiny spherules composed of very micro, less than 0.05mm acicular crystals. The spherules are perhaps 0.25mm in diameter.
Ceruleite from Emma Luisa mine, Guanaco, Antofagasta, Chile
Dark sky blue, solid crystalline.
Ceruleite from Wheal Maid, Gwennap, Redruth dist., Cornwall, England
Sky blue tiny micro crystals with good coverage.