EIFELITE

    Class : Silicates
    Subclass : Cyclosilicates
    Crystal system : Trigonal
    Chemistry : KNa3Mg4Si12O30
    Rarity : Very rare

Eifelite is an extremely rare silicate from the milarite group which constitutes a series with roedderite. It is found in blocks of gneissic xenoliths ejected by leucite tephrites from a volcano. Its name comes from its place of discovery : the Bellerberg volcano near Ettringen in the Eifel Massif (Germany). It is only known in small crystals of 1 mm maximum, colorless or faintly tinted with green or yellow.

Main photo : Eifelite from Caspar quarry, Ettringen, Mayen-Koblenz, Germany © Stephan Wolfsried

Eifelite in the World

Eifelite is only present in the xenoliths of the Belleberg volcano in the Caspar and Rothenberg quarries; its crystals do not exceed one millimeter.

Right photo : Eifelite from Caspar quarry, Ettringen, Mayen-Koblenz, Germany © Stephan Wolfsried

Eifelite in France

Ehrleite is not present in the French underground.

Twinning

No twin known for this mineral species.

Fakes and treatments

No fake listed for this mineral species.


Hardness : 5 to 6
Density : 2.67
Fracture : Undeterminated
Streak : White

TP : Transparent
RI : 1.543 to 1.546
Birefringence : 0.001
Optical character : Uniaxial +
Pleochroism : None
Fluorescence : None

Solubility : Insoluble


Magnetism : None
Radioactivity : None