Hausmannite
 
Locality: N'Chwaning II Mine, Northern Cape, South Africa

Size: 48 mm x 41 mm, 80 grams
 
A showy Hausmannite specimen with the unique metallic black crystals in asociation with pinkish brown Andradite Garnet.
 
Hausmannite is a relatively rare mineral, a Manganese oxide that belongs to the spinel group and forms tetragonal crystals, metallic brown to black in colour. Hausmannite is a complex oxide, or a mixed oxide, of manganese containing deposits. Andradite, is a mineral species of the garnet group. It is a nesosilicate, with formula Ca3Fe2Si3O12.
 
The Kalahari Manganese Field (KMF) is situated in the Northern Cape Province of South Arica. It comprises sedimentary manganese layers interbedded with banded iron formations of up to 2.2 billion-year-old. It is one of the largest known manganese-ore deposits in the world. The mines from this area is world-renowned for producing some top-quality and world-class specimens  along with a large variety of unique mineral species. Specimens from these mines are higly collectable.