Albite: from the Latin albus, meaning white. A mineral belonging to the Feldspar Group, the Sodium end-member of the Plagioclase series, with the chemical formula NaAlSi3O8. It crystallizes in the Triclinic System of the Trimetrical Group, with crystals that are flat and tabular, typically rectangular with a square cross-section and pinacoidal terminations. Often exhibits twinning. Color: white, sometimes colorless with shades of blue, orange, yellow, or blue-green. Transparency: ranges from translucent to opaque. Luster: vitreous or dull. Origin and occurrence: an essential component of many rocks, found in Granites, Pegmatites, and Syenites. Also present in hydrothermal vein deposits and in metamorphic rocks such as Phyllites, Mica Schists, and Gneisses.
