Chemist originally sold new mineral for facial blemish (4,4)

I believe the answer is:

cold sore

'facial blemish' is the definition.

'chemist originally sold new mineral' is the wordplay.
'originally' says to take the initial letters.
'new' is an anagram indicator.
'mineral' becomes 'ore' (ore is a kind of mineral**).
The first letter of 'chemist' is 'c'.
'sold' anagrammed gives 'olds'.
'c'+'olds'+'ore'='COLD SORE'

'for' acts as a link.

(Another definition for cold sore that I've seen is " Facial outbreak of herpes virus".)

I've seen this clue in The Guardian.

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