Corundum and Achroite Physical Properties
Tenacity
Brittle
Not Available
Solubility
insoluble
Not Available
Durability
Not Available
Not Available
Specific Gravity
3.90-4.05
2.90-3.40
Fracture
Uneven, Uneven, Gems, Difficult, Fibrous
Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001)
Cleavage
None – parting in 3 directions
Not Available
Chemical Composition
Al 2O 3Arthur Thomas , Gemstones (2009)
Na(Li 1.5Al 1.5)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012) Formula given for elbaite.
Corundum and Achroite Chemical Formula
While comparing Corundum and Achroite physical properties, the important data you should know is its chemical composition. Since chemical formula defines the molecular structure of the crystal, most of the physical properties like color, tenacity, solubility are governed by Corundum and Achroite chemical formula.
- Chemical formula of Corundum- Al 2O 3Arthur Thomas , Gemstones (2009)
- Chemical formula of Achroite- Na(Li 1.5Al 1.5)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012) Formula given for elbaite.
Corundum and Achroite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Corundum and Achroite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Corundum and Achroite Optical Properties during the identification of gemstone. Specific gravity of Corundum is 2.90-3.40 whereas that of Achroite is 2.90-3.40.