Blue John Diamond 9ct Yellow Gold Necklace. P992C. This stunning and sophisticated necklace boasts an unmissable cabochon cushion shaped piece of rare Blue John stone that has been sourced directly from Treak Cliff Cavern in Castleton. The stone is placed within an exquisite 9ct yellow gold setting and crowned by an enchanting 0.10ct diamond set on the bail. The pendant hangs gracefully off a matching delicate 9ct yellow gold chain completed with a classic lobster 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. 9ct Yellow Gold, Blue John and 0.10ct Diamond.