How to Facet a Rubellite Tourmaline

Helpful information on how to cut and polish Rubellite Tourmaline stones. Essential guides, tips and details necessary for Rubellite Tourmaline faceting.

1 Minute Read

Cornered - Nigerian rubellite tourmaline
A 9.07-ct, 13.5 x 8.6mm deep Cornered, cut from top Nigerian rubellite tourmaline by Jeff Graham.

Rubellite faceting can be a very rewarding experience due to the rarity and brilliance of the stone.

Rubellite Vs. Ruby

A rubellite tourmaline is often confused with ruby due to its red color. However, they are completely different gemstones. While they both offer red and pink hues, a closer look reveals that rubellites are transparent while rubies offer a much richer color. This is due to different physical and optical properties. Generally, rubellite is rarer than most rubies.

ColorRed/Purple/PinkAll varieties of red 
Moh's Hardness7-7.5 9
Refractive Index1.616-1.652 1.757-1.779
Critical Angle38.23° 34.62°
Specific Gravity3.02-3.26 3.99-4.1
CleavageNone None
FractureUneven, small conchoidal Conchoidal
Dispersion017 0.013
Heat SensitivityNot usually a problemCan be but usually not a problem
DichroicStrong (many color variations) Strong, especially in darker colors
Birefringencedouble refraction: medium (.014-.024) Double refraction: weak (0.018)
Crystal structureHexagonal Hexagonal (Trigonal)

Rubellite Treatments

Heat is sometimes used to lighten rubellite rough and get rid of undesirable color. Radiation is used on cut stones to improve color, but it is not commonly used on the rough. Usually rubellite stones are cut first and then irradiated.

Rubellite Faceting Comments

First, rubellite cuts and polishes like any other tourmaline, and usually there are no unique problems for this stone. Orientation is important, so choose the best color stone that you can find. However, you need to be careful about over saturation because sometimes stones can be dark.

Second, let's talk about polishing! A helpful tip is that I prefer polishing rubellite with alumina oxide with a tin lap (scored).

Finally, when faceting, any tourmaline design will work well. I generally prefer a shallow checkerboard on darker rough. Pick a design with the correct depth for the rough you have. Here is another helpful trick: light rough deep design, dark rough shallower design.

Rubellite Faceting: Gem Design Suggestions

Signature #4 - This is good for about any rough
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

Jeff R. Graham

The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as Gram Faceting Designs.

Never Stop Learning

When you join the IGS community, you get trusted diamond & gemstone information when you need it.

Become a Member

Get Gemology Insights

Get started with the International Gem Society’s free guide to gemstone identification. Join our weekly newsletter & get a free copy of the Gem ID Checklist!