Gaidonnayite

Formula:  Na₂ZrSi₃O₉ ^. 2H₂O

Origin of name:  For Gabrielle Donnay, Canadian crystallographer

Crystal system:  Orthorhombic

Crystal class:  mm2

Twinning:

Unit cell:

Colour:  Colourless to white

Diaphaneity:

Luster:  Vitreous

Habit:  Crystals bladed, elongated

Hardness:  5

Specific gravity:  2.67

Cleavage:  None

Tenacity:

Streak:  white

Synonyms/varieties:

Comments:  Dimorphous with catapleiite