Mould, perhaps in fine abalone (6)
I believe the answer is:
former
'mould' is the definition.
(a mould shapes or forms something)
'in fine abalone' is the wordplay.
'in fine' becomes 'f' (abbreviation. I am not sure about the 'in' bit.).
'abalone' becomes 'ormer' (ormer is a kind of abalone).
'f'+'ormer'='FORMER'
'perhaps' acts as a link.
(Other definitions for former that I've seen before include "Ex-" , "The first of two, earlier" , "One shaping" , "The first mention of the two" , "Core for winding an electrical core" .)