Elbaite Tourmaline Facet / Faceting Information


Brilliant Per cut in ElbiateElbiate Tourmaline

Color: Green/red/pink, watermelon (green outside red inside like the fruit)
Moh’s hardness: 7-7.5
Refractive Index: 1.616-1.652
Critical Angle: 38.23°
Specific Gravity: 3.02-3.26
Cleavage: None
Fracture: Uneven, small conchoidal
Dispersion: .017
Heat Sensitivity: Moderate
Dichroic: Strong (many color variations)
Birefringence (double refraction): Medium (.014-.024)
Crystal Structure: Hexagonal

Treatments: Generally there is no treatments with this kind of rough…

What I prefer to polishing with: Alumina oxide with a tin lap (scored).

Jeff’s Comments: Cuts and polishes like any other Tourmaline, usually no problems… Orientation is important, be very careful because the colors will sometime mix and the color distinctions will be lost.

Design Notes: Care must be taken, generally choose a design the will not mix the colors… My Smith Bar is a good choice for any bi color type of rough, because the ends are designed to be steep and not mix color(s) from the “c” axis.

Design Links:
Easy Emerald – This is a classic and works well on poor “c” axis colored stones
Smith Bar – This is a classic and works well on poor “c” axis colored stones

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.