Rhodochrosite
From Wikipedia, the free encyclopedia.

Rhodochrosite is a carbonate mineral with chemical composition MnCO₃. It has a rose-red colour, its hardness varies between 3,5 and 4,5. It crystallizes in the trigonal system.

Main use is as source for manganese, but some jewellery is made from it, especially in Argentina.

The original article can be found at: http://en.wikipedia.org/wiki/Rhodochrosite.
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