Voggite

Formula: Na₂Zr(PO₄)(CO₃)(OH).2H₂O

Origin of name: for Albert Vogg, Canadian amateur mineralogist of Montreal

Crystal system: Monoclinic

Crystal class: 2/m

Twinning:

Unit cell: a = 12.251, b = 6.557, c = 11.755, β = 116.12°

Colour: Colourless to white

Diaphaneity: Transparent to translucent

Luster: Vitreous

Habit: Crystals elongate 0.01 x 0.01 x 1 mm in matted nests, needle-like pseudohexagonal crystals

Hardness: 

Specific gravity: 2.70

Cleavage: 1; {010} poor

Tenacity: Brittle

Streak: White

Synonyms/varieties:

Comments:  Blue cathodeluminescence under electron beam