Prehnite
Prehnite is a calcium aluminium silicate that generally occurs as volcanic cavity infillings.
It occurs in numerous localities in the Kimberley region of Western Australia as well as across the border into the Northern Territory.
There are vast volcanic plains known as the "Antrim Plateau Volcanics" in the above mentioned region.
In places prehnite nodules weather out of the decomposed basalt and can be found lying on the surface or concentrated in creek systems.
