Silver Blue John Marcasite Marquise Beaded Shoulder Ring. R753. This simple and stylish ring boasts a delicate oval shaped cabochon of Blue John stone that has been sourced directly from Treak Cliff Cavern in Castleton. The stone has been placed within an exquisite sterling silver setting detailed with dazzling marcasite on the shoulders, bringing a sophisticated sparkle to the piece. The ring is completed by a classic sterling silver band. All our Blue John jewellery is designed and crafted within our very own workshops in Ashbourne, Derbyshire where a team of skilled craftsmen turn the raw Blue John stone into these stunning pieces of jewellery. You can find other matching Blue John jewellery and other Blue John rings on our website. Silver Blue John Marcasite Marquise Beaded Shoulder Ring