Mention ornament in conversation? (6)
I believe the answer is:
broach
'mention' is the definition.
(as in broaching a topic)
'ornament in conversation?' is the wordplay.
'ornament' becomes 'brooch' (brooch is a kind of ornament).
'in conversation?' indicates a 'sounds like' (homophone) clue (I've seen 'in conversation' mean this).
'brooch' is a homophone of 'BROACH'.
(Other definitions for broach that I've seen before include "Raise (a sensitive subject)" , "Start to speak" , "Raise (a subject) for discussion" , "Bring up for discussion" , "Begin" .)