In ejecta and certain alkaline rocks. Its chemical formula is CaSiO₃, with the structural formula Ca₃[Si₃O₉]. The theoretical chemical composition is: CaO 48.25%, SiO₂ 51.75%.
Wollastonite is a chain-like metasilicate mineral, characterized by a triclinic crystal system and fine tabular crystals, with aggregates occurring in radial or fibrous forms. Its unique crystal morphology and crystalline structure determine its properties, including non-toxicity, resistance to acids and alkalis, low moisture absorption, low oil absorption, low electrical conductivity, excellent insulation, high whiteness, good thermal stability and dimensional stability, as well as superior mechanical and electrical performance. It is a natural, green, low-carbon, and energy-efficient industrial mineral raw material.