Blue john shrovetide engraved limited edition cufflinks cl467 celebrate the local game with these shrovetide limited edition cufflinks that boast stunning round pieces of cabochon blue john that have been directly sourced from treak cliff cavern in castleton the stone is set within sterling silver settings that have been engraved with shrovetide football ashbourne around the edge so you can show off your support for the ashbourne tradition all our blue john jewellery is designed and crafted