The Doctor's earring

You may be looking for the Doctor's ear cuff, worn by the Thirteenth Doctor. A large earring was kept in a trunk within the Doctor's TARDIS. Shortly after his regeneration, the Second Doctor retrieved this earring, which he described as "very fashionable once", and recalled that he used to wear it "at one time". (PROSE: The Power of the Daleks)

Behind the scenes

 * The original rehearsal script by David Whitaker for TV: The Power of the Daleks (then known as The Destiny of Doctor Who) stated that the Doctor renewed before, and that last time, he was wearing a metal bracelet stored in a drawer of the console, also containing a large earring he used to wear at some point. (DWMSE 4) The earring and bracelet were described in John Peel's novelisation of the serial.