Caswellsilverite
A sodium chromium sulphide from enstatite meteorites.
Key facts
- Formula
- NaCrS2
- Family
- Sulphides
- Crystal system
- Trigonal
- First described
- the Norton County aubrite, 1982
Caswellsilverite was described in 1982 from the Norton County aubrite, which fell in Kansas and Nebraska in 1948. It is named after Caswell Silver, an American geologist who supported meteorite research. It is known only from meteorites.
What it is
Caswellsilverite is a layered sulphide of sodium and chromium. Sodium and chromium both normally prefer oxygen, so this mineral is another sign of the oxygen-starved conditions in which enstatite meteorites formed.
Where it is found
It occurs in Norton County with other unusual sulphides.
How it is recognised
It is microscopic and identified by microprobe analysis.
Did you know?
Norton County is the largest aubrite known, with a main mass of about a tonne.
Its fall in 1948 was seen as a brilliant fireball over the American Midwest.