Copper going to South American city to find antique? (5)
I believe the answer is:
curio
'antique?' is the definition.
(thesaurus)
'copper going to south american city' is the wordplay.
'copper' becomes 'cu' (chemical symbol).
'going to' is a charade indicator (letters next to each other).
'south american city' becomes 'rio' (I've seen this before).
'cu'+'rio'='CURIO'
'to find' is the link.
(Other definitions for curio that I've seen before include "bit of bric-a- brac" , "'Rare, unusual object (5)'" , "Antique" , "Rare and unusual item" , "Item of bric-a-brac" .)