Flat metal piece, gold, to remain at stable price (7)
I believe the answer is:
plateau
'flat' is the definition.
(thesaurus)
'metal piece gold to remain at stable price' is the wordplay.
I cannot really see how this works, but
'metal' could be 'la' (La is an example) and 'la' is found within the answer.
'piece' could be 'p' (abbreviation for Pawn) and 'p' is present in the answer.
'gold' could be 'au' (Au is the chemical symbol for gold) and 'au' is found within the answer.
The remaining letters 'te' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for plateau that I've seen before include "Paul, eat! (anag)" , "Elevated flat land" , "one has no inclination" , "Levelling off" , "High tableland" .)