Blue john heart 9ct yellow gold necklace p1554rthis exquisite necklace boasts a stunning cabochon heart shaped piece of rare blue john stone that has been sourced directly from treak cliff cavern in castleton the stone has been placed within a mesmerising 9ct yellow gold heart setting that hangs gracefully from a matching yellow gold chainrall 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