1 Physical Properties
1.1 Tenacity
1.2 Solubility
Not Available
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
2.60-2.652.50-3.00
1
7.18
1.5 Fracture
Uneven, Uneven, Gems, Sixth Edition (2006), Uneven, Conchoidal
Uneven-Conchoidal, ConchoidalWalter Schumann, Gemstones of the world (2001)
1.6 Cleavage
Perfect on {001}, very good on {010}, imperfect on {110}
3,6
1.7 Mohs Hardness
1.8 Chemical Composition
NaAlSi 3O 8Michael OâDonoghue , Gems, Sixth Edition (2006)
The chief constituent Lapis Lazuli is Lazurite, with the following chemical formula: (Na,Ca)8Al6Si6O24(S,SO)4