Ardaite

General Information:
 Chemical Formula:
Pb19Sb13S35Cl7
 Composition:
(Molecular Weight = 6,890.03 gm)
Antimony 22.97 % Sb
Lead 57.14 % Pb
Sulfur 16.29 % S 
Chlorine 3.60 % Cl
 Empirical Formula:
Pb19Sb13S35Cl7
 IMA Status:
Approved IMA 1980
 Locality:
Madjarovo, Arda River, Bulgaria.
 Name Origin:
Named for the locality.
Physical Properties:
 Color:
green gray.
 Diaphaniety:
Opaque
 Habits:
Microscopic Crystals - Crystals visible only with microscopes., Acicular - Occurs as needle-like crystals., Aggregates - Made of numerous individual crystals or clusters.
 Hardness:
2.5-3 - Finger Nail-Calcite
 Luster:
Metallic
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