A rough diamond? Not Di! (5)

I believe the answer is:

damon

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'a rough diamond? not di' is the definition.
I can't judge whether this defines the answer.

'rough diamond? not di' is the wordplay.
'rough' indicates anagramming the letters (a rough or broken ordering of the letters).
'not' is a deletion indicator.
'diamond' with 'di' removed is 'amond'.
'amond' with letters rearranged gives 'DAMON'.

Can you help me to learn more?

(Other definitions for damon that I've seen before include "faithful friend" , "Pythias's friend" , "Writer Runyon's first name" , "Matt --, US actor" .)

I've seen this clue in the Evening Standard.

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