Catapleiite

Formula:  Na₂ZrSi₃O₉ ^. 2H₂O

Origin of name:  For Greek for wholly and full

Crystal system:  Monoclinic, pseudo-hexagonal

Crystal class:    2/m

Twinning:  Polysynthetic by at least sic twin laws

Unit cell: 12.78 Ǻ, b = 7.42 Ǻ, c = 20.16 Ǻ, β = 90.4°

Colour:  Light yellow to yellowish brown to brown, salmon

Diaphaneity:

Luster:  Vitreous, greasy or dull

Habit:  Crystals thin hexagonal plates; lamellar masses

Hardness:  5 to 6

Specific gravity:  2.74

Cleavage:  4; {10-10} perfect, {10-11} and {10-12} imperfect, {000-1} parting

Tenacity:  Brittle

Streak:  White, pale yellow

Synonyms/varieties:

Comments:  Series with calcium catapleiite; dimorphous with gaidonnayite