trigonal synthetic synthetic corundum
Flux-Grown Ruby (Crystal)
Al2O3:Cr
Quick Facts
Hardness
9.0
Specific Gravity
3.99
Refractive Index
1.762
Optical Character
Uniaxial -
Crystal Structure
#! Species: Flux-Grown Ruby
#! System: Trigonal (-3m)
#! Habit: Tabular to prismatic from flux growth
trigonal[-3m]:{10-10}@1.0 + {10-11}@0.8 + {0001}@0.5
trigonal
-3m
{10-10} {10-11} {0001}
Physical Properties
Crystal Systemtrigonal
Hardness (Mohs)9.0
Specific Gravity3.99
CleavageNone (parting on {0001} and {10-11})
FractureConchoidal
LustreVitreous to adamantine
Optical Properties
Refractive Index1.762
Birefringence0.008
Optical CharacterUniaxial -
Dispersion0.018
Pleochroismstrong: purplish-red / orangey-red
FluorescenceStrong red (LW and SW UV)
Origin & Identification
Originsynthetic
Growth Methodflux
ManufacturerChatham, Kashan, Knischka, Ramaura
First Produced1960
Diagnostic FeaturesFlux remnants (wispy veils, fingerprints of flux), platinum platelets from crucible, characteristic flux feather inclusions, may contain twisted veils resembling natural silk
Colours
RedPinkish-red
Common Inclusions
Flux remnants (wispy veils)Platinum plateletsFlux fingerprints
Interactive Preview
Open this crystal in the CDL Playground to rotate, export, and explore in 3D.
Open in Playground #! Species: Flux-Grown Ruby
#! System: Trigonal (-3m)
#! Habit: Tabular to prismatic from flux growth
trigonal[-3m]:{10-10}@1.0 + {10-11}@0.8 + {0001}@0.5
Natural Counterpart
The natural gem this synthetic imitates
Related Minerals
Other minerals in the trigonal system
