Blue john pendant oval surrounded with diamonds 18ct white gold p2665 this mesmerising pendant boasts a stunning oval shaped piece of rare blue john stone that has been sourced directly from the derbyshire blue john cavern in castleton the stone is placed within an exquisite 18ct white gold setting and surrounded by glistening 010ct brilliant cut diamonds giving the piece a sophisticated sparkle all our blue john jewellery is designed and crafted within our very own workshops in ashbourne