Bits of wisdom (6)
I believe the answer is:
pearls
'bits of wisdom' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for pearls that I've seen before include "Lustrous structures found in oysters" , "Don't cast these jewels before swine" , "Lustrous structures in bivalves" , "types" , "Stones" .)