Garronite

Formula:  Na₂Ca₅Al₁₂Si₂₀O₆₄ ^. 27H₂O

Origin of name:  Locality; Garron Plateau, Antrim, Ireland

Crystal system:  Tetragonal

Crystal class: -42m

Twinning:

Unit cell:

Colour:  Colourless, white, tan, yellow

Diaphaneity:

Luster:  Vitreous

Habit:  Radiating aggregates, compact masses

Hardness:  4.5

Specific gravity:  2.13 to 2.17

Cleavage:  2; 90° to each other and parallel to length of crystals

Tenacity:

Streak:

Synonyms/varieties:

Comments: