Tenacity
Brittle
-
Solubility
-
-
Durability
-
-
Specific Gravity
5.6-5.762.50-2.80
1
7.18
👆🏻
Fracture
Uneven
-
Cleavage
[001] perfect; [100] distinct
Perfect
Mohs Hardness
2.5-35-6.5
2
10
👆🏻
Chemical Composition
Pb 5Cu 2(SO 4) 3(CO 3)(OH) 6Anthony et al , Handbook of mineralogy (2001)
Na 4(Al,Si) 12O 24Cl to Ca 4(Si,Al) 12O 24(CO 3,SO 4)Arthur Thomas , Gemstones (2009)