9ct Yellow Gold Blue John Toscana Side Marquise Ring. R513. Part of our stylish Toscana collection, this contemporary ring features a striking marquise shaped cabochon of fine Blue John stone, sourced directly from Castleton, Derbyshire. The highly polished gemstone is complimented by a raised 9ct yellow gold frame and a classic band 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: 12mm x 4mm.