witherite

Witherite is a barium carbonate mineral, BaCO3, in the aragonite group. Witherite crystallizes in the orthorhombic system and virtually always is twinned. The mineral is colorless, milky white, grey, pale yellow, green, to pale brown. The specific gravity is 4.3, which is high for a non-metallic mineral. It fluoresces light blue under both long and short-wave UV and is phosphorescent under short-wave UV light.
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(n.)
Barium carbonate occurring in white or gray six-sided twin crystals, and also in columnar or granular masses.
  

General Information:
 Chemical Formula:
BaCO3
 Composition:
(Molecular Weight = 197.34 gm)
Barium 69.59 % Ba
Carbon 6.09 % C 
Oxygen 24.32 % O 
 Empirical Formula:
Ba(CO3)
 Name Origin:
Named after the English natural historian, W. Withering (1741-1799).
Physical Properties:
 Cleavage:
[010] Distinct
 Color:
colorless, milky white, grayish white, pale yellowish white, or pale brownish white.
 Density:
4.3
 Diaphaniety:
Subtransparent to translucent
 Habits:
Pseudo Hexagonal - Crystals show a hexagonal outline., Columnar - Forms columns, Reniform - "Kidney like" in shape (e.g.. hematite).
 Hardness:
3-3.5 - Calcite-Copper Penny
 Luminescence:
None.
 Luster:
Vitreous (Glassy)
 Streak:
white
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Eng: witherite
Urdu: بیرِیَم کاربونیٹ ۔ ایک سُفید بھُورا مَعدنی مادَہ ۔