Color: Colorless, yellow, green, blue, pink, purple, red and orange
Moh’s Hardness: 4
Refractive Index: 1.434
Critical Angle: 44.37°
Specific Gravity: 3.18
Cleavage: Perfect in 4 directions
Fracture: Even to conchoidal, brittle
Dispersion: .007
Heat Sensitivity: High, in my experience
Birefringence (double refraction): None
Crystal Structure: Isometric
Treatments: Generally none, sometimes can be irradiated.
What I prefer to polishing with: Flourite is not something I cut, recommended polishes are wax lap with Alumina or tin oxide or chrome oxide Ultralap. Orient the table about 10 degrees off the crystal face to reduce cleavage problems.
Jeff’s Comments: Cuts pretty easily, and can be a tough to polish. Watch the heat when dopping… Typically has silk and cleavage problems
Design Notes: About any designs will work well…
This edited version of an article by the late Jeff Graham is part of a special archived informational series from Gram Faceting. Used with permission.
