Sterling silver blue john 10mm round stud earrings e099 these classic 10mm stud earrings are part of our handmade heritage collection and boast two striking cabochon of blue john stone that have been sourced directly from treak cliff cavern in castleton the stones are framed within classicsterling silver settingsandare completed by simplepost and butterfly fastenings for easy wear all our blue john jewellery is designed and crafted within our very own workshops in ashbourne derbyshire w