Cameca's brooch was a piece of jewellery given to the First Doctor by his fiancee, Cameca, as he and his companions prepared to depart 15th century Mexico. (TV: The Aztecs)
The First Doctor later used the brooch to buy suits and top hats for himself and Steven Taylor in London in 1912. (AUDIO: The Suffering) However, it re-entered his possession, as the Second Doctor found it in a chest in the TARDIS immediately after regenerating. (PROSE: The Power of the Daleks) The Seventh Doctor later wore it on the lapel of his cream linen suit. (PROSE: White Darkness) The Eighth Doctor later gave the brooch to his granddaughter Susan Foreman as a Christmas present. (AUDIO: Relative Dimensions)