Orthoclase "Pig's Egg" Pseudomorph

Kaolinite after Orthoclase
Goonbarrow China Clay Pit ,
Bugle, Treverbyn, Cornwall
 
86 x 50 x 26 mm
 
A pseudomorph of fine-grained muscovite ("sericite") with kaolinite after orthoclase feldspar, found in kaolinized granite.
The Orthoclase is a good sized Carlesbad twinned crystal with a super dusting of shiny muscovite on some areas.
The crystal is sharply defined and a great example despite being incomplete (see photos).
 
Colloquially known by the name  of 'Pig's Eggs' by the local miners and collectors, these are classics for the area around the China clay pits of the St. Austell mining area of Cornwall.