A Slytherin family heirloom, this golden locket was first owned by Salazar Slytherin and eventually came into the possession of the Gaunt family. Notable for its green glittering 'S' on the front, the locket was sold by Merope Gaunt when her father and brother were sent to Azkaban. It eventually made its way into the hands of Tom Riddle, who used it for darker purposes, transforming it into a Horcrux. The Slytherin locket was shown to put dark thoughts into the wearer's mind.