Sunstone (Feldspar)

 

Color: Sunstone Colorless, champagne, Schiller (copper inclusions, usually used for cabochons), Multi colored (green, blue, red, orange), red

Moh’s Hardness: 6-6.5

Refractive Index: 1.52-1.568

Critical Angle: 41.14°

Specific Gravity: 2.56-2.70

Cleavage: Perfect

Fracture: Uneven, somewhat brittle

Dispersion: Low (.012)

Heat Sensitivity: Moderate in my experience

Dichroism: Weak

Birefringence (double refraction): Weak to medium (.005-.01)

Crystal Structure: Triclinic

 

Treatments: Generally none