Minerals from the Kalahari manganese fields of South Africa have become almost impossible to get hold of since the mine owners clamped down and forbade the miners to remove specimens. This is from the Nchwaning II mine.
Kutnohorite is a rare calcium manganese carbonate mineral with magnesium and iron that is a member of the dolomite group. It forms a series with dolomite, and with ankerite.
|Dimensions||2.5 × 1.1 × 30 cm|