Rhodonite is a manganese inosilicate comprising the elements manganese, Iron and magnesium (Mn, Fe, Mg, Ca)SiO3. It is a member of the pyroxenoid group of minerals, crystallizing in the triclinic system. The name Rhodonite derives from the Greek ῥόδος rhodos, rosy), although it can look brown due to surface oxidation. Rhodonite hardness is 5.5–6.5 on the Mohr scale, and the specific gravity is 3.4–3.7. The manganese is often partly replaced by iron, magnesium, calcium, and sometimes zinc. Sold in single pieces