Heliophyllite

General Information:
 Chemical Formula:
Pb6As2O7Cl4
 Composition:
(Molecular Weight = 1,646.85 gm)
Arsenic 9.10 % As
Lead 75.49 % Pb
Chlorine 8.61 % Cl
Oxygen 6.80 % O 
 Empirical Formula:
Pb6As2O7Cl4
 Environment:
Secondary mineral.
 Locality:
Langban, Harstig, and Jakobsverg mines, Varmland Sweden.
 Name Origin:
Named from the Greek for "sun" and "leaf', in reference to its color and structure.
Physical Properties:
 Cleavage:
[011] Good
 Color:
greenish yellow or yellow.
 Density:
6.89
 Diaphaniety:
Translucent
 Habits:
Massive - Granular - Common texture observed in granite and other igneous rock., ,
 Hardness:
2 - Gypsum
 Luster:
Vitreous - Greasy
 Streak:
light yellow
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