Paraumbite

Formula: K₃Zr₂HSi₆O₁₈.nH₂O

Origin of name: from Greek para = similar and umbite

Crystal system: orthorhombic

Crystal class: 222

Twinning: 

Unit cell: 

Colour: colourless to white

Diaphaneity: 

Luster: vitreous to pearly on cleavage

Habit: crystals equant to 1 mm, massive

Hardness: 4.5

Specific gravity: 2.26 to 2.59

Cleavage: 2; {010} perfect, {100} good

Tenacity: 

Streak: white

Synonyms/varieties:

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