Scolecite

Formula: CaAl₂Si₃O₁₀.3H₂O

Origin of name: from Greek for worm

Crystal system: monoclinic

Crystal class: m

Twinning: common on {100} about [001] axis, contact (fishtail) or penetration

Unit cell: a = 9.85 Å, b = 18.96 Å, c = 6.52 Å, b = 110.1°

Colour: colourless, white

Diaphaneity: transparent

Luster: vitreous, silky when fibrous

Habit: crystals slender prismatic, vertically striated, divergent groups, commonly twinned, fibrous radiated masses

Hardness: 5

Specific gravity: 2.27

Cleavage: 1; {110} perfect

Tenacity: uneven, brittle

Streak: 

Synonyms/varieties:

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