Pollucite

Formula: (Cs,Na)₂Al₂Si₄O₁₂.H₂O

Origin of name: from Pollux, the mythological brother

Crystal system: cubic

Crystal class: 4/m -3 2/m

Twinning: 

Unit cell: 

Colour: colourless, white, gray, pinkish, bluish, violet

Diaphaneity: transparent

Luster: vitreous to greasy

Habit: crystals cubic, dodecahedral, rare, massive, fine-grained

Hardness: 6.5 to 7

Specific gravity: 2.94

Cleavage: none

Tenacity: 

Streak: 

Synonyms/varieties:

Comments: series with analcime