18ct White Gold Blue John Medium Oval Signet Ring, R189. This classic signet style ring features a stunning hand carved Blue John stone, sourced directly from Castleton, Derbyshire. The gemstone is set within a solid band of 18ct white gold. The finished piece is smooth and highly polished.  All our Blue John jewellery is designed and crafted within our very own workshops in Ashbourne, Derbyshire where a team of skilled craftsmen transform natural Blue John into these stunning pieces of jewellery. You can find other matching Blue John jewellery on our website and in our stores. This item will arrive lovingly and securely dispatched in our elegant jewellery packaging. Dimensions Blue John; 10mm x 12mm, Width of Band; 3mm