Silver blue john oblong twist ring r001 this contemporary ring is part of our heritage handmade jewellery collection and boasts an stunningoblong shaped cabochon of the finest blue johnstone that has been sourced locally from the treak cliff cavern in castletonthe stone is set within a simple sterling silver frame and completed with a classic sterling silver band all our blue john jewellery is designed and crafted within our very own workshops in ashbourne derbyshire where a team of skil