RHODONITE (miniature)

Rhodonite is a manganese inosilicate mineral with the chemical formula (Mn, Fe, Mg, Ca)SiO3, belonging to the pyroxenoid group. It crystallizes in the triclinic system and is typically found in cleavable to compact masses that exhibit a rose-red color, a name derived from the Ancient Greek word ῥόδον (rhódon), meaning 'rose.' This vibrant hue often appears brownish due to surface oxidation, with the rose-red color attributed to the presence of manganese cation (Mn2+).

Rhodonite crystals are characterized by a thick tabular form, although they are not commonly found. The mineral exhibits perfect prismatic cleavage, nearly at right angles. Its hardness ranges from 5.5 to 6.5, and it has a specific gravity between 3.4 and 3.7. The luster is vitreous, though it can occasionally appear pearly on cleavage surfaces. Manganese in rhodonite is frequently partially substituted by iron, magnesium, calcium, and sometimes zinc, which can be present in significant quantities. A greyish-brown variety that contains up to 20% calcium oxide is known as bustamite, while fowlerite is a zinc-rich variety that includes 7% zinc oxide.