Achroite and Caledonite Physical Properties
Specific Gravity
2.90-3.40
5.6-5.76
Fracture
Uneven, ConchoidalWalter Schumann
Uneven
Cleavage
Indiscernible
[001] perfect; [100] distinct
Mohs Hardness
7-7.5
2.5-3
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.
Pb 5Cu 2(SO 4) 3(CO 3)(OH) 6Anthony et al , Handbook of mineralogy (2001)
Achroite and Caledonite Chemical Formula
While comparing Achroite and Caledonite 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 Caledonite 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 Caledonite- Pb 5Cu 2(SO 4) 3(CO 3)(OH) 6Anthony et al , Handbook of mineralogy (2001)
Achroite and Caledonite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Achroite and Caledonite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Achroite and Caledonite Optical Properties during the identification of gemstone. Specific gravity of Achroite is 5.6-5.76 whereas that of Caledonite is 5.6-5.76.