Fur in bales? (5)

I believe the answer is:

sable

I'm a little stuck... Click here to teach me more about this clue!

'fur' is the definition.
(I know that sable is a type of fur)

'bales?' is the wordplay.
'bales' can be anagrammed to 'SABLE'.
Though, I am not sure how this is indicated.

'in' acts as a link.

Can you help me to learn more?

(Other definitions for sable that I've seen before include "Black (heraldry); fur" , "Antelope, fur" , "Brush" , "Black; antelope" , "Fur - heraldic black" .)

I've seen this clue in the Evening Standard.

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