Calcium, sodium, potassium, magnesium, iron, and aluminum are all silicates. Zinc, manganese, and titanium impurities can occur occasionally. At cleavage angles of 87o and 93o, the crystal system is more cohesive, transparent, and prismatic. (Characteristic of minerals in the pyroxene group) At clear angles, it is also visible. The crystal structure is often transparent and light-colored. It is also prismatic, with a 93-degree cleavage angle. The structure goes from light green to colorless.
