Sep
07
Sillimanite
Sillimanite is an aluminosilicate mineral with the chemical formula Al2SiO5. Sillimanite is named after the American chemist Benjamin Silliman (1779–1864). It was first described in 1824 for an occurrence in Chester, Middlesex County, Connecticut, US. It’s well known to gem collectors and highly prized because of its great scarcity. It is Orthorhombic crystal system mineral […]