Crossword Genius

Diamond, perhaps? It is real, surprisingly, set around ring (9)

Ross

I believe the answer is:

solitaire

'diamond' is the definition.
(I've seen this before)

I don't understand the rest of the clue.

(Other definitions for solitaire that I've seen before include "[PATIENCE], especially in America" , "American singer" , "One-gem ring; one-player game" , "Single stone in jewellery" , "Bond girl" .)

I've seen this clue in The Times.
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