JARLITE
Class : Halides
Subclass : Oxyfluorides
Crystal system : Monoclinic
Chemistry : Na(Sr,Na)7MgAl6F32(OH,H2O)2
Rarity : Very rare
Jarlite is an extremely rare fluoride known in geodes from the famous cryolite pegmatite of Ivigtut (Greenland). It was named in honor of the President of the Danish Cryolite Company who discovered the mineral. Jarlite forms small elongated tabular crystals of 1 mm, commonly grouped in spherolitic aggregates or rosettes, colorless, white, gray, rarely yellow, as well as small masses.
Main photo : Jarlite from Ivigtut Mine, Greenland © Gianfranco Ciccolini
Jarlite in the World
Twinning
No twin known for this mineral species.
Fakes and treatments
No fakes recorded for this mineral species.
Hardness : 4 to 4.5
Density : 3.78 to 3.93
Fracture : Irregular
Streak : White
TP : Translucent to transparent
RI : 1.429 to 1.436
Birefringence : 0.007
Optical character : Biaxial (+/-)
Pleochroism : None
Fluorescence : None
Solubility : Insoluble
Magnetism : NoneRadioactivity : None