Rhodochrosite

Color: Rosy-red to pink

Moh’s Hardness: 3.3-3.7

Refractive Index: 1.60-1.82

Critical Angle: 38.68° for low RI and 33.33° for high RI

Specific Gravity: 3.30-3.70

Cleavage: Perfect in 3 directions

Fracture: Uneven, conchoidal, brittle

Heat Sensitivity: Moderate

Birefringence (double refraction): Very strong (.22)

Crystal Structure: hexagonal, trigonal

Treatments: Generally none