Blue john necklace round silver p218rthis simple and stunning necklace boasts an unmissable cabochon round piece of rare blue john stone that has been sourced directly from treak cliff cavern in castleton the stone is set within exquisite sterling silver and hangs gracefully from a delicate sterling silver chain complete with a classic bolt ring clasprall our blue john jewellery is designed and crafted within our very own workshops in ashbourne derbyshire where a team of skilled craftsmen t