Achroite and Andradite Physical Properties
Tenacity
Not Available
Brittle
Solubility
Not Available
Not Available
Durability
Not Available
Not Available
Specific Gravity
2.90-3.40
3.70-4.10
Fracture
Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001)
Conchoidal, Uneven, Conchoidal, Brittle, ConchoidalArthur Thomas, Gemstones (2009)
Cleavage
Not Available
none
Mohs Hardness
7-7.5
6.5-7
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.
Ca 3Fe 2(SiO 4) 3Arthur Thomas , Gemstones (2009)
Achroite and Andradite Chemical Formula
While comparing Achroite and Andradite 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 Andradite 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 Andradite- Ca 3Fe 2(SiO 4) 3Arthur Thomas , Gemstones (2009)
Achroite and Andradite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Achroite and Andradite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Achroite and Andradite Optical Properties during the identification of gemstone. Specific gravity of Achroite is 3.70-4.10 whereas that of Andradite is 3.70-4.10.