Rhodochrosite mineral. Rhodochrosite is a manganese carbonate mineral (MnCO3), typically coloured rose-red, with shades of pale brown or (as here) pink. Rhodochrosite is found with other manganese minerals as a hydrothermal vein mineral in low-temperature ore deposits. The crystalline habitat is either rhombohedral and/or scalenohedral. Its main use is as an ore of manganese, but attractively banded specimens are often used for decorative stones and jewellery. This sample, from the Sweet Home Mine near Alma, Colorado, USA, is 22 centimetres wide.