trigonal Synthetic synthetic corundum
Flux-Grown Sapphire (Crystal)
Al2O3:Fe,Ti
Crystal Structure
#! Species: Flux-Grown Sapphire
#! System: Trigonal (-3m)
#! Habit: Tabular crystal from flux growth
trigonal[-3m]:{10-10}@1.0 + {10-11}@0.8 + {0001}@0.5
trigonal
-3m
{10-10} {10-11} {0001}
Quick Facts
Hardness
9.0
Specific Gravity
3.99
Refractive Index
1.762
Optical Character
Uniaxial -
Physical Properties
Crystal Systemtrigonal
Hardness (Mohs)9.0
Specific Gravity3.99
FractureConchoidal
LustreVitreous to adamantine
Optical Properties
Refractive Index1.762
Birefringence0.008
Optical CharacterUniaxial -
Dispersion0.018
Pleochroismstrong: violetish-blue / greenish-blue
FluorescenceInert to weak
Origin & Identification
OriginSynthetic
Growth MethodFlux
ManufacturerChatham
First Produced1970
Diagnostic FeaturesFlux remnants (wispy veils), platinum platelets, characteristic flux fingerprint inclusions, no natural silk
Colours
BluePadparadschaYellow
Common Inclusions
Flux remnantsPlatinum plateletsFlux fingerprints
Natural Counterpart
The natural gem this synthetic imitates
Related Minerals
Other minerals in the trigonal system
