Cowlesite

Formula:  CaAl₂Si₃O₁₀ ^. 5-6H₂O

Origin of name:  For John Cowles, American mineralogist and collector

Crystal system:  Orthorhombic

Crystal class:  222

Twinning:

Unit cell: a = 11.27 Å, b = 15.25 Å, c = 12.61 Å

Colour:  Colourless to white

Diaphaneity:

Luster:  Pearly

Habit:  Crystals bladed, microscopic

Hardness:  2

Specific gravity:  2.05

Cleavage: 1; {010} perfect

Tenacity:

Streak:

Synonyms/varieties:

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