Blue john diamond 9ct yellow gold necklace p097rthis stunning and sophisticated necklace boasts an unmissable oval shaped cabochon piece of rare blue john stone that has been sourced directly from treak cliff cavern in castleton the stone is set within an exquisite 9ct yellow gold frame and backed by enchanting mother of pearl stone the pendant hangs gracefully from a matching yellow gold chain complete with a bolt ring clasp for easy wearrall our blue john jewellery is designed and crafted