White gold stolen by climber (5)
I believe the answer is:
ivory
'white' is the definition.
(ivory is a kind of white)
'gold stolen by climber' is the wordplay.
'gold' becomes 'or' ('or' is the heraldic name for gold).
'stolen by' means one lot of letters goes inside another.
'climber' becomes 'ivy' (I've seen this before).
'or' placed into 'ivy' is 'IVORY'.
(Other definitions for ivory that I've seen before include "Creamy-white colour" , "Smooth material of elephant tusks" , "Piano key" , "Creamy colour" , "recluse's tower?" .)