Sanctuary, Cabalis Nocturnum Ring

original movie prop

In first season episode Fata Morgana, Dr. Magnus and the Sanctuary team revive three women from an ancient burial crypt.  Although their memories are originally fragmented, symbols on rings worn by the three identify them as associated with the Cabalis Nocturnum, a secret society intent on capturing and controlling Abnormals and other ancient beings of power.  The women are eventually discovered to be the Morrigan, legendary Arthurian witch goddess sisters of war and strife, capable of changing the course of battle by their very presence on the field.

Gold painted metal ring with three crowns on the face and additional markings on the band.

From Legends Memorabilia.