Tag «kyanite»

Al2SiO5 (Polymorphs) minerals

Al2SiO5/Polymorphs Group of Minerals: The three important minerals of this group are ; Andalusite Sillimanite Kyanite These minerals occur in metamorphosed luminous rocks, such as pelitic schists. (1). Andalusite (Al2SiO5): Physical properties of Andalusite: Crystal System: Andalusite occurs in orthorhombic crystal form. Cleavage: Andalusite has a poor cleavage. Fracture: Uneven fracture Hardness: Andalusite has a …