Sterling Silver Blue John Oval Ring. R076. This contemporary ring features a stunning oval cabochon of the finest Blue John stone which has been sourced directly from Castleton, Derbyshire. The gemstone is set in a wide sterling silver band with a perfect, highly polished finish. A beautiful addition to any jewellery lover\'s collection. All our Blue John jewellery is designed and crafted within our very own workshops in Ashbourne, Derbyshire where a team of skilled craftsmen transform natural pieces of Blue John into these stunning pieces of jewellery. You can find other matching Blue John jewellery on our website. All articles purchased from C W Sellors are lovingly and securely dispatched with our elegant jewellery packaging. Dimensions: Blue John: 14mm x 10mm, Width of band at back: 4mm.