9ct Yellow Gold Blue John Medium Oval Band Ring. R012. This striking statement ring, part of our Heritage handmade jewellery collection features a hand carved oval Blue John stone that has been sourced directly from the Treak Cliff Cavern in Castleton. The stone is framed by highly polished 9ct Yellow Gold and completed with a solid, wide statement band. 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 rings on our website. Dimensions: Blue John Stone 21x11mm, width of band at back 6mm.