Island copper gets qualification (4)

I believe the answer is:

cuba

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'island' is the definition.
(Cuba is an example)

'copper gets qualification' is the wordplay.
'copper' becomes 'Cu' (Cu is the chemical symbol for copper).
'gets qualification' becomes 'ba' (I can't explain this - if you can you should give a lot more credence to this answer).
'cu'+'ba'='CUBA'

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(Other definitions for cuba that I've seen before include "Castro's republic" , "Fidel's place" , "Caribbean island republic" , "Island country involved in a 1962 missile crisis" , "Island S. of Florida" .)

I've seen this clue in The Guardian.

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