Cryolite

History: First described prior to 1959; first published in 1799.

Tests: Fuses readily, produces a yellow flame and virtually invisible in water.

Uses: Pottery glazes and certain types of glass.

Properties
Cleavage None
Color Colorless, white, pale brown, pink, smoky to black
Crystal Systems Monoclinic
Fracture Uneven
Hardness 2.5
Specific Gravity 2.97

Group

Halides

Composition

Na3AlF6