Achroite and Covellite Physical Properties
Tenacity
Not Available
Flexible
Solubility
Not Available
Not Available
Durability
Not Available
Not Available
Specific Gravity
2.90-3.40
4.6-4.76
Fracture
Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001)
Gemstones (2009), UnevenArthur Thomas, Gemstones (2009), Brittle, Metallic
Cleavage
Not Available
Perfect on {0001}
Mohs Hardness
7-7.5
Not Available
Chemical Composition
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.
CuSMichael OâDonoghue , Gems, Sixth edition (2006) More from other references
Achroite and Covellite Chemical Formula
While comparing Achroite and Covellite 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 Achroite and Covellite chemical formula.
- 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.
- Chemical formula of Covellite- CuSMichael OâDonoghue , Gems, Sixth edition (2006) More from other references
Achroite and Covellite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Achroite and Covellite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Achroite and Covellite Optical Properties during the identification of gemstone. Specific gravity of Achroite is 4.6-4.76 whereas that of Covellite is 4.6-4.76.