Gadolinium Gallium Garnet. A synthetic gemstone used as an early diamond substitute. GGG is manufactured by the Czochralski method and can be manufactured in many colors. With its specefic gravity og 7,5 it is a lot denser then a diamond while being a lot softer (6.5 - 7.5 on Mohs scale).

Gemological Information of Gadolinium Gallium Garnet "GGG"
Color Colorless to light brown or yellow
Crystal structure Cubic
Refractive index 1.970(+.060)
Durability Fair to Good
Hardness 6.5
Similar stones GGG can be confused with: Diamond, Zircon, Strontium Titanate, Sphene, CZ & YAG. SG, Spectrum, Magnification and Dispersion can be used to separate GGG from other similar material.
Treatments None
Country of origin Man-Made Material
GGG care
Ultrasonic cleaning Safe
Steam cleaning Usually Safe
Warm soapy water Safe
Chemical attack Not Attacked
Light sensitivity Turns Brown Slowly with UV Light Exposure
Heat sensitivity Not Sensitive