A plagioclase feldspar, the fifth member of the Albite-Anorthite solid solution series. Bytownite is rare, and normally occurs in small grains in lime-rich igneous rocks. Clear pale yellow crystals have come from Mexico and Oregon. ,Chemical composition: Calcium sodium aluminum silicate, ,Physical properties: Mohs Hardness: 6.0 Specific gravity: 2.74 Color: White, pale yellow, shades of gray Luster: glassy Fracture: conchoidal Cleavage: two good at about 94ยบ to each other Habit: Triclinic - pinacoidal. Crystals are rare.
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