1 Physical Properties
1.1 Tenacity
1.2 Solubility
Not Available
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
2.50-3.002.60-2.65
1
7.18
1.5 Fracture
Uneven-Conchoidal, ConchoidalWalter Schumann, Gemstones of the world (2001)
Uneven, Uneven, Gems, Sixth Edition (2006), Uneven, Conchoidal
1.6 Cleavage
3,6
Perfect on {001}, very good on {010}, imperfect on {110}
1.7 Mohs Hardness
1.8 Chemical Composition
The chief constituent Lapis Lazuli is Lazurite, with the following chemical formula: (Na,Ca)8Al6Si6O24(S,SO)4
NaAlSi 3O 8Michael OâDonoghue , Gems, Sixth Edition (2006)