Sterling Silver Blue John Marcasite Large Oval Beaded Edge Stud Earrings. E1637. These simple and stylish stud earrings feature two oval cabochons of fine Blue John stone that have been sourced directly from the Treak Cliff Cavern in Castleton. The stones are set within simple sterling silver frames that have been embellished by Marcasite stones which add a vintage style sparkle. The earrings are completed by classic post and butterfly fastenings for easy wear. All our Blue John jewellery is designed and crafted within our very own workshops in Ashbourne, Derbyshire where a team of skilled craftsmen turn the raw Blue John stone into these stunning pieces of jewellery. You can find other matching Blue John jewellery and other Blue John earrings on our website. Dimensions: 13mm x 12mm, Blue John; 7mm x 6mm.