Gold props up economy when Spain slumps - congratulations from its neighbour (7)
I believe the answer is:
chapeau
'slumps congratulations from its neighbour' is the definition.
I can't judge whether this defines the answer.
'gold props up economy when spain' is the wordplay.
'gold' becomes 'Au' (Au is the chemical symbol for gold).
'props up' says to put letters next to each other.
'economy when' becomes 'chap' (I can't explain this - if you can you should give a lot more credence to this answer).
'spain' becomes 'e' (abbreviation for Espana).
'chap'+'e'='chape'
'au' put after 'chape' is 'CHAPEAU'.
Can you help me to learn more?
(Other definitions for chapeau that I've seen before include "(French) hat" , "something to put on noodles" , "Fashionable hat" , "Cap (French or heraldic?)" .)