Onyx
From Tardis Wiki, the free Doctor Who reference
Onyx was a shade of black, which shared its name with a gemstone.[source needed]
Captain Latimer wore an onyx black cravat in 1892. (TV: The Snowmen [+]Loading...["The Snowmen (TV story)"])
John Lumic wore an onyx black cravat up to when he was converted into a Controller of the Cybus Cybermen. (TV: Rise of the Cybermen [+]Loading...["Rise of the Cybermen (TV story)"], The Age of Steel [+]Loading...["The Age of Steel (TV story)"])
Mr Song wore a single-breasted waistcoat of onyx black brocade with a notched collar when he met River Song. (AUDIO: Signs [+]Loading...["Signs (audio story)"])