Sterling silver blue john marcasite double row stone necklace p2133 this stylish necklace features ahighly polishedmarquiseshaped cabochon of fine blue johnstone that has been sourced directly from the treak cliff cavern castleton in derbyshire the stone has been placed within a vintage style sterling silver setting embellished by two layers of marcasite stones giving an elegant and sparkly finish to the piece the pendant hangs gracefully from a fluid 18 inch longsterling silver chain