Akdalaite

Formula: 4Al₂O₃^.H₂O

Origin of name:  Locality; Akdala, region of Karagandin, Kazakhstan.

Crystal system:  Hexagonal

Crystal class:  6 or 622

Twinning:

Unit cell: a = 12.87 Å, c = 14.97 Å

Colour:  White

Diaphaneity: Translucent

Luster:  Vitreous to porcelaneous

Habit:  Crystals tabular, elongated, tiny, hexagonal section; lens-like or nest-like aggregates.

Hardness:  7-7.5

Specific gravity:  3.68

Cleavage:  None

Tenacity: Brittle

Streak: White

Synonyms/varieties:

Comments: Occurrence in veinlets cutting amesite-fluorite-muscovite rocks and fluorite-magnetite-diopside-vesuvianite skarns.