Blue john necklace owl with marcasite eyes p2322 set within the eyes and belly of this cute and quirky owl pendant are three stunning round pieces of rare blue john stone that has been sourced directly from treak cliff cavern in castleton the sterling silver owl design is further embellished by glistening marcasite set around the blue john in the eyes giving the piece a touch of sophisticated sparkle the pendant hangs gracefully off a delicate sterling silver chain complete with a classic b