Mary Collins's necklace
Type: Amber necklace
Appearances: The Dragon's Call
An amber necklace provided the sorceress Mary Collins with the magical energy necessary to cast various spells and enchantments.

Among these, she used it to perform a teleportation spell that helped her avoid being seized by Uther, a glamour, that she used to take on the form of Lady Helen, and a powerful sleeping enchantment that put the entire court of Camelot to sleep, except for Merlin due to his magic (The Dragon's Call).