Crossword Genius

One of fifty diamonds, it's said (6)

Ross

I believe the answer is:

stated

'said' is the definition.
('state' can be a synonym of 'say')

'one of fifty diamonds' is the wordplay.
'one of fifty' becomes 'state' (I've seen this in another clue).
'diamonds' becomes 'd' (abbreviation in bridge say).
'state'+'d'='STATED'

'it's' acts as a link.

(Other definitions for stated that I've seen before include "Said firmly, averred" , "Definitely expressed" , "Set forth (in words)" , "Uttered, expressed in words" , "Put in words, said" .)

I've seen this clue in The Times.
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