At the front, the castle is a lovely shade of pink...
-- although whether this is from some sort of render or paint,
or just another from of stone being used, is hard to tell.

It's probably stone: as Sir Matthew Arundell -- as part of his 'makeover'... -- had the medieval front redesigned by Robert Smythson:
with the aim of making the castle look even more imposing, as well as reinforcing the impression
of long-inherited family power and wealth.