Crystal System: Monoclinic
Status of Occurrence: Confirmed Occurrence
Distribution: Uncommon
Chemical Composition: Aluminium silicate hydroxide
Chemical Formula: Al2Si2O5(OH)4
Method(s) of Verification: Aberfan Borehole - associated with dickite, XRD at the Natural History Museum (X-ray no. 1901F); Trimsaran Borehole No. 2 - XRD at the Natural History Museum (X-ray no. 1902F).

Chemical Group:

  • Silicates

Geological Context:

  • Hydrothermal
Introduction: a member of the kaolinite-serpentine group and polymorphous with dickite, halloysite and kaolinite. Typically of hydrothermal origin.
Occurrence in Wales: identified in strata of Coal Measures age from two borehole cores at the Natural History Museum, London.

Key Localities:

  • South Wales Coalfield: identified in Coal Measures age strata from Trimsaran Borehole No. 2, Kidwelly, Carmarthenshire (registered as 1985 GM MI 29620) and associated with dickite in rock core from a depth of '380 to 382' feet in the Aberfan Borehole, Mid Glamorgan (1985 GM MI 33153).

There are no key localities for this specimen.


There are no references for this specimen.