Franconite

Formula:  Na₂Nb₄O₁₁ ^. 9H₂O

Origin of name:  From locality; Francon Quarry, Quebec, Canada

Crystal system:  Monoclinic

Crystal class:  Unknown

Twinning:

Unit cell: a = 22.21, b = 12.87, c = 6.35, β = 92.24°

Colour:  White

Diaphaneity:

Luster:  Vitreous

Habit:  Crystals, bladed forming globules average 150 µm across

Hardness: 4

Specific gravity:  2.72

Cleavage:  [001] parting

Tenacity:

Streak:  White

Synonyms/varieties:

Comments: