Silver Blue John Marcasite Oval Lace Edge Necklace. P2122. This elegant necklace features a highly polished oval shaped cabochon of rare Blue John stone that has been sourced directly from Treak Cliff Cavern in Castleton. The stone is set within the centre of an intricately crafted sterling silver pendant, embellished by lace detailing and marcasite stones, giving the piece a sparkly and sophisticated finish. The pendant hangs gracefully from a fluid 18 inch long sterling silver chain completed by a classic bolt ring clasp 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 necklaces on our website. Silver Blue John Marcasite Oval Lace Edge Necklace. Pendant 45x24mm including bale.