Sterling Silver Blue John Marcasite Oval Art Deco Necklace. P2125. This romantic, vintage style pendant features a highly polished cabochon of the finest Blue John stone that has been sourced directly from the Derbyshire Blue John Cavern in Castleton. The stone is set within the centre of a sterling silver pendant embellished with dazzling marcasite stones, giving the piece a sophisticated sparkle. The pendant hangs from an 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 stylish pieces of jewellery. You can find other matching Blue John jewellery and other Blue John necklaces on our website. Pendant 32 x 15mm including bale.