Dadsonite

General Information:
 Chemical Formula:
Pb21Sb23S55Cl
 Composition:
(Molecular Weight = 8,950.53 gm)
Antimony 31.29 % Sb
Lead 48.61 % Pb
Sulfur 19.70 % S 
Chlorine 0.40 % Cl
 Empirical Formula:
Pb21Sb23S55Cl
 IMA Status:
Approved IMA 1969
 Locality:
Giant property, Yellowknife, NWT, Canada.
 Name Origin:
Named for Alexander S. Dadson (1906-1958), Canadian mineralogist.
Physical Properties:
 Color:
lead gray or gray.
 Density:
5.68 - 5.76, Average = 5.72
 Diaphaniety:
Opaque
 Habits:
Fibrous - Crystals made up of fibers., ,
 Hardness:
2.5 - Finger Nail
 Luster:
Metallic
 Streak:
black
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