Nasonite

General Information:
 Chemical Formula:
Pb6Ca4Si6O21Cl2
 Composition:
(Molecular Weight = 1,978.92 gm)
Calcium 8.10 % Ca
Silicon 8.52 % Si
Lead 62.82 % Pb
Chlorine 3.58 % Cl
Oxygen 16.98 % O 
 Empirical Formula:
Pb6Ca4Si6O21Cl2
 Environment:
Metamorphosed Mn-Zn deposit.
 Locality:
Franklin, Sussex Co., New Jersy, USA.
 Name Origin:
Named for Frank Lewis Nason (1856-1928), American geologist, Geological Survey of New Jersey.
Physical Properties:
 Cleavage:
[???] Good
 Color:
white.
 Density:
5.5
 Diaphaniety:
Transparent to translucent
 Habits:
Massive - Granular - Common texture observed in granite and other igneous rock., Cleaveable - Easily cleaved into fragments.,
 Hardness:
4 - Fluorite
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous - Adamantine
 Streak:
white
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