Cashmere

Cashmere was fine, soft wool, originally that from the Kashmir goat.

The Eleventh Doctor wore a frock coat of eggplant purple cashmere when travelling with Clara Oswald; (TV: The Bells of Saint John, etc) most notably when helping to foil the 1562/2013 Zygon Invasion of Earth and when revisting the Fall of Gallifrey on the final day of the Last Great Time War, (TV: The Day of the Doctor) and before and after the Siege of Trenzalore. (TV: The Time of the Doctor) His successor, the Twelfth Doctor, wore it during his first hours. (TV: The Time of the Doctor, Deep Breath)

The Spy Master wore an overcoat of plum purple cashmere. (TV: Spyfall, Ascension of the Cybermen|The Timeless Children)