Coronadite

Formula: Pb(Mn4+6Mn3+2)O16

Species:

Colour: Dark gray, black

Lustre: Metallic, Sub-Metallic, Dull, Earthy

Hardness: 4½ – 5

Specific Gravity: 5.246 – 5.505

Crystal System: Monoclinic

Member of: Coronadite Group > Hollandite Supergroup

Name: Named in 1905 by Waldemar Lindgren in recognition of Francisco Vasquez de Coronado (1510 – 1554), a famous Spanish explorer of the American southwest.

Type Locality: Horse-Shoe shaft (Horseshoe Mine), Coronado Mine (Coronado Mining Co. property; Arizona Copper Co. group [in part]), Coronado vein, Copper Plate Gulch, Greenlee County, Arizona – USA

Isostructural with: Cryptomelane, Ferrihollandite, Hollandite, Manjiroite, Strontiomelane