Cryolite (Na3AlF6)-Lump

Characteristic

 

Cryolite (Na3AlF6, sodium hexafluoroaluminate) is an uncommon mineral identified with the once-large deposit at Ivittuut on the west coast of Greenland, depleted by 1987.




Formula： Na3•AlF6

Formula mass：209.9 g mol−1

Color：Colorless to white, also brownish, reddish and rarely black

Dana classification：11.6.1.1

Crystal system：Monoclinic

Crystal habit：Usually massive, coarsely granular. The rare crystals are equant and pseudocubic

Tenacity：Brittle

Mohs scale hardness：2.5 to 3

Melting point：1012 °C

Solubility：Soluble in AlCl3 solution, soluble in H2SO4 with the evolution of HF, which is poisonous. Insoluble in water.

 


Application

 

Mainly used as fluxing agent in the production of aluminum electrolysis, also used as additive to the wear-resisting of abrasive products, iron alloy and the flux of rimming steel, non-ferrous metal flux, casting deoxidizer, enamel of emulsifier, glass opal agent, welding flux and ceramics filler. Aluminum- metallurgy. This chemical is used as adhesives, cosolvent in enamel industry.