Certificate number 38-1821-CO-PR-8451-16
Certificate number
38-1821-CO-PR-8451-16
Issue date
2016-05-11
Mineral Specie
Corundum
Variety
Sapphire
Mineral Specie
Corundum
Variety
Sapphire
Origin
Natural
Chemical composition
Aluminium oxide
Crystal system
Rhombohedral
Habit
Hexagonal bypiramid in different inclinations. Both ends of many crystals are capped by flat basal faces
Colour
According to GIA GEmSet: G 7/1 green, dark, grayish
Cutting Style
Oval
Measurements
9.04x7.01x3.97 mm
Weight
2.46 ct
Luster
Vitreous
Transparency
Transparent
Refractive indices
1.770 - 1.762
Birrefringence
0.008
Optic sign
-
Hardness
9 Mohs
Cleavage
None
Density
3.90
Absortion spectra absorción
Due to iron
Picture
Comments
Straight colour bands.
Tiny particles forming feathers.
Extremately tiny particles forming feathers. Darkfield illumination, 40X.