Gadolinium Gallium Garnet Faceting Information
Gadolinium Gallium Garnet or GGG, is a crystalline material of the garnet group which may also find use in jewelry as a gemstone or a diamond stimulant.
Gadolinium Gallium Garnet (GGG) Color: Colorless, yellow, green, blue, pink, purple, red and orange
Moh's Hardness: 7
Refractive Index: 1.97 - 2.02
Critical Angle: 30.51°
Specific Gravity: 7.02
Cleavage: None
Fracture: Conchoidal
Dispersion: .045
Heat Sensitivity: Low
Birefringence (double refraction): None
Crystal Structure: Isometric
Treatments: None
What I prefer to polishing with: Tin lap with Alumina oxide. Zinc laps with 8,000 pre-polish and 50,000 polish.
Jeff's Comments: Cuts and polishes like Garnet. It is quite pretty especially in clear and light colors.
Design Links: 4-Way Stop - This is great for saturated rough if you have a piece that will work in the shape…
Princess - Nice in about any material
Brilliant Pear - Good in any color
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.
Related Articles
Garnet Value, Price, and Jewelry Information
How Do Garnets Form?
Garnet Symbolism
Top Spots for Gem Hunting in the US
Latest Articles
A Guide to Early Victorian Romantic Period Jewelry
Malaya or Malaia Garnet Value, Price, and Jewelry Information
Choosing Your First Gemstones: A Rough Guide for Faceters
Gemstone Coatings: CVD and More
Never Stop Learning
When you join the IGS community, you get trusted diamond & gemstone information when you need it.
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!