18ct white gold blue john 053 carat diamond cushion top ring r897 this enchanting ring boasts astrikingcushion shaped piece of rare blue john stone that has been directly sourced from treak cliff cavern in castleton the stone is set within exquisite 18ct white gold and surrounded bya sparkling array of053ct brilliant cut diamonds that frame the blue john stone and run down the split shoulders finishing in a classic band all our blue john jewellery is designed and crafted within our ve