Rhodochrosite

Rhodochrosite is MnCO₃, a carbonate mineral of manganese. This sample is about 7x7 cm and is from Sweet Home mine, Alma, Colorado. All these specimens are displayed in the Smithsonian Museum of Natural History.

Rhodochrosite is a member of the calcite group of carbonates along with Smithsonite and siderite.

Rhodochrosite crystals can have great beauty, but they are relatively soft and brittle and don't serve well in everyday use as gems.

This rhodochrosite gem at left is 11.2 carats and is from Catamarca, Argentina. Those at right are 27.8 and 21.3 carats and are from Hotazel, Cape Province, South Africa.

The gems at left are 20.8 and 13.3 carats and are from from Hotazel, Cape Province, South Africa. The one at right is 15.2 carats and is from N'Chwaning mine, Hotazel, Cape Province, South Africa.

The sample above is about 4x4 cm and is from Hotazel, Cape Province, South Africa.