Blue john silver round cufflinks cl004 these stylish cufflinks boast stunning round pieces of cabochon blue stone that has been directly sourced from treak cliff cavern in castleton the stone is set within a sterling silver base and completed by a classic twist fastening for easy wear all our blue john jewellery is designed and crafted within our very own workshops in ashbourne derbyshire where a team of skilled craftsmen turn the raw blue john stone into these sophisticated pieces of jewel