trigonal Synthetic synthetic corundum
Synthetic Ruby (Verneuil) (Boule)
Formula Al2O3:Cr
Crystal Structure
#! Species: Synthetic Ruby (Verneuil)
#! System: Trigonal (-3m)
#! Habit: Corundum habit from flame fusion boule
trigonal[-3m]:{10-11}@1.0 + {0001}@0.4
trigonal
-3m
{10-11} {0001}
Quick Facts
Hardness
9.0
Specific Gravity
3.99
Refractive Index
1.762
Optical Character
Uniaxial -
Physical Properties
- Crystal System
- trigonal
- Hardness (Mohs)
- 9.0
- Specific Gravity
- 3.99
- Cleavage
- None (parting on {0001} and {10-11})
- Fracture
- Conchoidal
- Lustre
- Vitreous to adamantine
Optical Properties
- Refractive Index
- 1.762
- Birefringence
- 0.008
- Optical Character
- Uniaxial -
- Dispersion
- 0.018
- Pleochroism
- strong: purplish-red / orangey-red
- Fluorescence
- Strong red (LW and SW UV)
Origin & Identification
- Origin
- Synthetic
- Growth Method
- Flame Fusion
- First Produced
- 1902
- Diagnostic Features
- Curved striae, spherical gas bubbles, uniform colour distribution, no natural inclusions (silk, rutile needles)
Characteristics
Colours
RedPinkish-red
Common Inclusions
Curved striaeGas bubblesUnmelted alumina powder
Natural Counterpart
The natural gem this synthetic imitates
Related Minerals
Other minerals in the trigonal system