9ct Yellow Gold Blue John Long Oval Celtic Necklace. P1391. This elegant necklace features hand carved Blue John that has been sourced directly from Castleton, Derbyshire. The highly polished Blue John marquise is framed within a unique 9ct yellow gold Celtic design. Sold complete with an 18 inch 9ct yellow gold chain which fastens with a classic bolt ring style clasp. All our Blue John jewellery is designed and crafted within our very own workshops in Ashbourne, Derbyshire where a team of skilled craftsmen transform the natural Blue John into these stylish 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.