Anglesite

Anglesite is a lead sulfate mineral, PbSO4. It occurs as an oxidation product of primary lead sulfide ore, galena. Anglesite occurs as prismatic orthorhombic crystals and earthy masses, and is isomorphous with barite and celestine. It has a high specific gravity of 6.3 due to its lead content, 74 y mass; its hardness is 3. Color is white, gray with pale yellow streaks. It may be dark gray if impure.
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n. anglesite (mineral)

(n.)
A native sulphate of lead. It occurs in white or yellowish transparent, prismatic crystals.
  

General Information:
 Chemical Formula:
PbSO4
 Composition:
(Molecular Weight = 303.26 gm)
Lead 68.32 % Pb
Sulfur 10.57 % S 
Oxygen 21.10 % O 
 Empirical Formula:
Pb(SO4)
 Environment:
Secondary, weathered deposits of lead ore.
 Locality:
Tsumeb, Southwest Africa.
 Name Origin:
Named after the island of Anglesey (Wales, Great Britain).
Physical Properties:
 Cleavage:
[001] Good, [210] Distinct
 Color:
blue, colorless, green, gray, or yellow.
 Density:
6.3
 Diaphaniety:
Transparent to translucent
 Habits:
Granular - Generally occurs as anhedral to subhedral crystals in matrix., Stalactitic - Shaped like pendant columns as stalactites or stalagmites (e.g. calcite).,
 Hardness:
2.5-3 - Finger Nail-Calcite
 Luminescence:
None.
 Luster:
Adamantine
 Streak:
white
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ANGLESITE