PACHNOLITE
Class : Halides
Subclass : Fluorides
Crystal system : Monoclinic
Chemistry : NaCaAlF6 H2O
Rarity : Rare
Pachnolite is a secondary fluoride which is found in fluorinated pegmatites, and exceptionally in carbonatite. Its name comes from the Greek pachne (frost) because of its transparent appearance like ice. Pachnolite forms elongated, constantly twinned prisms measuring up to 8 cm, grainy and cleavable masses, sometimes stalactites or chalcedony-like masses; it is colorless or white. Pachnolite is commonly associated with other pegmatite fluorides (elpasolite, cryolite, sellaite, fluorite, etc...).
Main photo : Pachnolite from Ivigtut Mine, Greenland © Christian Rewitzer
Pachnolite in the World
Twinning
Twins are common on {100}, producing crystals with an orthorhombic appearance.
Fakes and treatments
No fakes listed for this mineral species.
Hardness : 3
Density : 2.983
Fracture : Irregular
Streak : White
TP : Translucent to transparent
RI : 1.411 to 1.420
Birefringence : 0.009
Optical character : Biaxial +
Pleochroism : None
Fluorescence : None
Solubility : Sulfuric acid
Magnetism : NoneRadioactivity : None