subs. phr. (common).—1.  Coals.

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  1849.  T. MILLER, Gabarni in London, 43. Were he even trusted with the favourite horse and gig to fetch a sack of BLACK DIAMONDS from the wharf.

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  2.  (old).—A rough but clever (or good) person; this has given place to ROUGH DIAMOND (q.v.).

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