Dark sword changing hands (5)

I believe the answer is:

sable

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

I can't explain the rest of the clue.

(Other definitions for sable that I've seen before include "Brush" , "Bales of valuable Russian fur" , "Dark brown fur of the marten" , "Adventurous courage" , "Bales (anag.)" .)

I've seen this clue in The Telegraph.

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