Sodium hexafluoroaluminate is a colorless crystalline solid. It has low solubility in water and organic solvents. Cryolite is a low-temperature alpha-form of sodium aluminofluoride. It is mined in significant quantities in Greenland, and in small amounts in elsewhere. Being melted cryolite is a good electrolyte and it is a good solvent for Al2O3 and other metal oxides.
Cryolyte is manufactured:
by interaction of Na2CO3 or NaF on Al(OH)3 or Al2O3 solution in HF;
by reaction of AlF3 and NaF;
by interaction of Al(OH)3 and Na2CO3 or NaAlO2 with water NH4F;
solvent (80-85% by mass of solution) for bauxite in the electrolytic production of aluminum;
in glass and enamel industries;
filler for bonded abrasives;