Microsommite

Formula:  (Na,Ca,K)_7-8 (Si,Al)₁₂O₂₄(Cl,SO₄,CO₃)_2-3

Origin of name:  From Greek for small

Crystal system:  Hexagonal

Crystal class:  6

Twinning: 

Unit cell: 

Colour:  Colourless

Diaphaneity: 

Luster:  Silky to brilliant on {10-10}

Habit:  Crystals, minute prismatic striated parallel to length

Hardness:  6

Specific gravity:  2.45

Cleavage:  2; {10-10} perfect, {0001} indistinct

Tenacity: 

Streak: 

Synonyms/varieties:

Comments: