Silver Whitby Jet Marcasite Triangle Ring. R820. This elegant ring boasts a striking marquise shaped cabochon of rare Whitby Jet stone that has been directly sourced from Whitby on the North East coast of Yorkshire. The stone is placed within an exquisite sterling silver diamond setting that has been embellished by dazzling marcasite stones which bring a sophisticated sparkle to the piece. The ring is completed by a classic sterling silver band. All our Whitby Jet jewellery is designed and crafted within our very own workshops in Ashbourne, Derbyshire where a team of skilled craftsmen turn the raw Whitby Jet stone into these stunning pieces of jewellery. You can find other matching Whitby Jet jewellery and other Whitby Jet rings on our website. Silver Whitby Jet Marcasite Triangle Ring. 29x16mm.