Cryolite – [Na3AlF6]

Cryolite is an extremely rare mineral at Mont Saint-Hilaire where only a few specimens have been recovered until now.

PHYSICAL CHARACTERISTICS:

 

  • Color is usually colorless to white.
  • Luster is greasy.
  • Diaphaneity is transparent to translucent.
  • Crystal System is monoclinic; P21/n.
  • Crystal Habits include sharp pseudo-octahedral crystal to 2mm.
  • Cleavage none distinct.
  • Fracture is uneven.
  • Hardness is 2.5.
  • Specific Gravity is approximately 2.97 g/cm3.
  • Streak is white.
  • Associated Minerals include aegirine, chabazite, eudialyte,
    lovozerite, natrolite, sodalite and villiaumite.
  • Distinguishing Features: Crystal habit.
  • Origin: Named in 1799 from the Greek cryo, for ice and stone,
    in allusion to the icelike appearance of the mineral.

 

 

Dana class # 11.6.1.1 – Halogenides; halide complexes; alumino-fluorides
Strunz class # III/B.3-30 – Halogenides; double halogenides without water, with [BF4]1-,[SiF6]2- and [AlF6]3- ;
cryolithionite – calcjarlite series