Gold-coloured alloy for decoration (6)
I believe the answer is:
ormolu
'gold-coloured alloy for decoration' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for ormolu that I've seen before include "Gold-coloured ally used in decoration" , "Decorative gilt alloy" , "Gold effect" , "Gilt brass" , "Gold-leaf" .)