Manasseite

Formula:  Mg₆Al₂(CO₃)(OH)₁₆ ^. 4H₂O

Origin of name:  For E. Manasse, Italian mineralogist

Crystal system:  Hexagonal

Crystal class:  6/m 2/m 2/m

Twinning: 

Unit cell: a = 3.104 Å, c = 15.32 Å

Colour:  White, pale bluish, grayish, brownish white

Diaphaneity: 

Luster:  Pearly, waxy

Habit:  Massive, foliated; lamellar

Hardness:  2

Specific gravity:  2.05

Cleavage:  1; {0001} perfect

Tenacity:  Laminae flexible, inelastic

Streak: 

Synonyms/varieties:

Comments:  Dimorphous with hydrotalcite