Rhodochrosite Facet / Faceting Information


Rhodochrosite CrystalsRhodochrosite

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

What I prefer to polishing with: Alumina on tin/lead or wax lap, or chrome oxide Ultralap

Jeff’s Comments: Faceting grade material is not common and seldom very big. Orient the stone to avoid cleavage planes and use a fine lap for cutting

Design Notes: About any Quartz or Tourmaline design will work well…

Gram Faceting Archive of Information
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.