9ct Yellow Gold Blue John Drilled Wide Triangle Necklace, PUNQ0001893. This contemporary necklace is part of our handmade Heritage jewellery collection and features a striking Blue John cabochon sourced directly from Castleton, Derbyshire. The gemstone is triangular shaped and set on a 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 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.