Cannonite Field of view 1 mm Locality: Cogolla Alta mine, La Ventosilla farmhouse, Belalcázar, Córdoba, Andalusia, Spain Description: White cannonite on bismuthinite (EDS confirmed). Collection and photograph Christian Rewitzer. — Photo: Christian Rewitzer · CC BY-SA 3.0
Cannonite
Cannonite is an IMA-recognized mineral species in the sulfate class, with the chemical formula Bi₂O(SO₄)(OH)₂.
It crystallizes in the monoclinic crystal system (space group P2_1/c).
Key properties: Mohs hardness 4; specific gravity 6.5; White streak; Adamantine luster.
IMA symbol Cnn, IMA status: approved, named in 1992.
An alteration product in Cu-Bi-Au-sulfide deposits.
It is found associated with Covellite, cuprobismutite, bismuthinite, quartz (Marysvale, Utah); bismuthinite, pyrite, arsenopyrite, cosalite, bornite, anglesite, micas (Italy).
The mineral was named to honor Benjamin Bartlett Cannon, V (b. 1950), amateur mineralogist of Seattle, Washington, USA, who recognized the first specimens.