Ruby (colour)

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Romana in her ruby dress. (TV: Meglos)

Ruby was a shade of red named after a certain gemstone.

Romana II wore a ruby dress during her encounter with Meglos. (TV: Meglos)

The Third Doctor wore a ruby cravat during the Solos Crisis. (TV: The Mutants)

The Fourth Doctor wore a ruby cravat as part of his detective outfit. (PROSE: Nanomorphosis, Evolution; AUDIO: The Merfolk Murders; COMIC: Gaze of the Medusa; TV: The Talons of Weng-Chiang)

The Seventh Doctor wore a ruby tie with his suit of cream linen during an adventure in the System. (PROSE: Sky Pirates!)

Nyssa wore ruby shoes during her second encounter with the Mara. (TV: Snakedance)