Labradorite is a feldspar gemstone known for displaying a stunning internal iridescence called “labradorescence,” a type of adularescence. This feature is sometimes called “schiller

Color: Typically colorless, white, yellow, or gray; May show red, orange, yellow, green, blue, and violet color flashes of labradorescence
Crystal structure: Triclinic
Luster: Pearly or vitreous (glass-like)
Transparency: Transparent to opaque
Refractive index: 1.52-1.57
Specific Gravity: 2.68-2.72
Cleavage: Perfect in two directions
Fracture: Uneven
Streak: White
Luminescence: May show fluorescence; red in SW-UV, light blue or violet-blue in LW-UV
Pleochroism: Present and notable in Oregon labradorite