Liebermannite
Potassium feldspar packed into the dense hollandite structure, found in a Martian meteorite.
Key facts
- Formula
- KAlSi3O8
- Family
- High-pressure minerals
- Crystal system
- Tetragonal
- First described
- the Zagami Martian meteorite, 2013
Liebermannite was approved as a new mineral in 2013 from the Zagami shergottite, which fell in Nigeria in 1962. It is named after Robert Liebermann, an American mineral physicist. It is known only from meteorites.
What it is
Liebermannite is the high-pressure form of potassium feldspar. In its hollandite structure, silicon and aluminium sit among six oxygen atoms, and potassium fills tunnels between the framework. It is the potassium partner of lingunite, the high-pressure form of sodium feldspar.
Where it is found
It was found in shock-melt pockets in Zagami, where grains of potassium feldspar were caught in the shock that launched the rock from Mars. It occurs with stishovite and other dense minerals.
How it is recognised
It is found with the electron microprobe and confirmed by electron backscatter diffraction, which distinguishes it from glass of the same composition.
Did you know?
Hollandite-type potassium feldspar may carry potassium deep into Earth's mantle in sinking slabs.
Zagami is also the type meteorite for zagamiite.