9ct yellow gold blue john toscana long marquise necklace p1613 this striking necklace is part of our toscana collection and features a stunning marquise shaped cabochon of rare blue john stone which has been sourced directly from treak cliff cavern in castleton 9ct yellow gold surrounds the blue john stone the pendant sits gracefully on an 18 inch 9ct yellow gold chain that is completed by a classic bolt ring clasp for easy wear all our blue john jewellery is designed and crafted within ou