Edingtonite

Edingtonite is a white, gray, brown, colorless, pink or yellow mineral. Its chemical formula is BaAl2Si3O10·4H₂O. It has varieties with tetragonal, orthorhombic or triclinic crystals.
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(n.)
A grayish white zeolitic mineral, in tetragonal crystals. It is a hydrous silicate of alumina and baryta.
  

General Information:
 Chemical Formula:
BaAl2Si3O10·4(H2O)
 Composition:
(Molecular Weight = 507.60 gm)
Barium 27.05 % Ba
Aluminum 10.63 % Al
Silicon 16.60 % Si
Hydrogen 1.59 % H 
Oxygen 44.13 % O 
 Empirical Formula:
BaAl2Si3O10·4(H2O)
 IMA Status:
Approved IMA
 Locality:
Kilpatrick Hills, near Glasgow, Dumbarton, Scotland.
 Name Origin:
Named after the discoverer of the mineral, Edington from Glasgow, Scotland.
Physical Properties:
 Cleavage:
[110] Perfect
 Color:
brownish gray, colorless, gray, white, or pink.
 Density:
2.69 - 2.7, Average = 2.69
 Diaphaniety:
Transparent to translucent
 Habits:
Pseudo Tetragonal - Crystals show a tetragonal shape., Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline)., Massive - Uniformly indistinguishable crystals forming large masses.
 Hardness:
4-5 - Fluorite-Apatite
 Luster:
Vitreous (Glassy)
 Streak:
white
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