Sterling Silver Blue John Slim Oblong Ring. R405. This simple and stylish ring boasts a stunning oblong shaped cabochon of the finest Blue John that has been sourced directly from the Treak Cliff Cavern in Castleton. The stone is placed within an exquisite sterling silver setting that sits on a classic 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. All articles purchased from CW Sellors are lovingly and securely dispatched with our elegant jewellery packaging. Matching items are available within this collection. Dimensions: Setting: 14mm x 6mm.