Lingunite
The dense hollandite-structured form of feldspar, found in shock veins of chondrites.
Key facts
- Formula
- NaAlSi3O8
- Family
- High-pressure minerals
- Crystal system
- Tetragonal
- First described
- the Sixiangkou L6 chondrite, early 2000s
Lingunite was described in the early 2000s from the Sixiangkou meteorite, an L6 chondrite that fell in China in 1989. It is named after Lin-gun Liu, a scientist who first made this structure in the laboratory.
What it is
Lingunite has the chemistry of albite feldspar packed into a much denser structure, the hollandite structure, in which silicon sits among six oxygens. It forms at pressures above about 20 gigapascals.
Where it is found
It occurs in and beside shock-melt veins in heavily shocked ordinary chondrites and in some Martian meteorites, usually where feldspar was melted and then crystallised under pressure.
How it is recognised
It is identified by Raman spectroscopy, which distinguishes it from feldspar glass and maskelynite.
Did you know?
Lingunite forms only in the hottest, highest-pressure parts of a shock vein.
A potassium-rich form of the same structure has been found in Martian meteorites.