Tenacity
-
-
Solubility
insoluble
-
Durability
-
-
Specific Gravity
6.46-6.573.03-3.18
1
7.18
👆🏻
Fracture
Uneven, ConchoidalWalter Schumann, Conchoidal
Uneven, Irregular, Conchoidal
Cleavage
Good [110] and [021]
{???} Indistinct
Mohs Hardness
3-3.57-7.5
2
10
👆🏻
Chemical Composition
PbCO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Na(Mg 3)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012)