Sterling Silver Blue John Marcasite Swirl Cross Necklace. P2132. This pointed cross pendant features a central hand carved round Blue John gemstone, sourced directly from Treak Cliff Cavern in Castleton, set on the Sterling silver cross with a decorative swirl detail and accented with sparkling Marcasite gemstones. The pendant hangs gracefully from a fluid 18 inch long sterling silver chain complete with 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. Dimensions: Pendant 45x28mm including bale.