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

Jarlite is known in the Ivigtut pegmatite (Greenland) as well as in the Valle del Cura (Argentina).

Jarlite in France

Jarlite is not present in the French underground.

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