a mineral, alumoborosilicate of calcium, iron, and manganese. Depending on the ratio of Fe²⁺ and Mn²⁺ present, the mineral is classified as “ferroaxinite,” “severge-nite,” or “manganosevergenite.” Axinite crystallizes in a triclinic system, and usually appears in the form of broad crystals with sharp points. Its hardness on the mineralogical scale is 6.5–7.0; its density is 3,250–3,300 kg/m³. Its color is mostly brown, often with a bluish or violet tint. Axinite is commonly found in close association with the ores of iron, copper, tin, and manganese and also with complex ores. The composition of axinite corresponds to the particular mineral paragenesis: manganous axinites accompany tin and polymetallic mineralization, while ferruginous axinites are characteristic of copper and iron deposits.