It might be spotty young fellow's character (10)

I believe the answer is:

bloodstone

'it might be spotty' is the definition.

'young fellow's character' is the wordplay.
'young fellow's' becomes 'bloods' (informal term for a young man).
'character' becomes 'tone' (I've seen this before**).
'bloods'+'tone'='BLOODSTONE'

(Another definition for bloodstone that I've seen is " Mineral".)

I've seen this clue in The Times.

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