These rings are made out of a black stone which harness a protection spell forged by a wiccan (Emily Bennett, the only one who knows how to produce them - they aren't recorded in the grimoires), and they were passed down from a Gilbert Family ancestor (originally a vampire hunter, named Johnathon Gilbert in the 1800s). It protects the wearer from any supernatural related death. For instance, if a vampire attacks and kills a person wearing this ring, the victim will revive from death in one to two hours.
The ring only protects pure humans (not witches, doppelgangers, or werewolves, or anything else with supernatural abilities). And it can only protect against supernatural related deaths.
There are only 2 rings in existence. It can not be duplicated by anyone other than a Bennett witch.
Canon characters protected by the ringsEdit
Alaric Saltzman (received the ring from Isobel before she was turned into a vampire)
Jeremy Gilbert (John Gilbert gave the other ring to him).