Fair to refine tin from Congo? (7)
I believe the answer is:
african
'from congo?' is the definition.
(eg from the Republic of the Congo)
'fair to refine tin' is the wordplay.
'to refine' indicates anagramming the letters (I've seen 'refined' mean this).
'tin' becomes 'can' (synonyms).
'fair' anagrammed gives 'afri'.
'afri'+'can'='AFRICAN'
(Other definitions for african that I've seen before include "Continental" , "Person from south of the Mediterranean" , "Like some elephants" , "Black" , "From one continent" .)