Sterling Silver Blue John Marcasite House Style Large Dragonfly Brooch. M322. Complementing our sterling silver and enamel designs, the introduction of sparkling and natural marcasite stones provides a classic and elegant way to accessorise any outfit. With a certain Art Deco feel, accompanied by Derbyshire Blue John and Garnets, the collection features wonderful insect earrings, brooches, rings and pendants. This unique dragonfly brooch is handmade in sterling silver. The wings feature four highly polished Blue John stones which have been sourced directly from the Treak Cliff Cavern in Castleton, framed with Marcasite stones. The intricately patterned silver body is also accented with sparkling Marcasite gemstones which add a vintage feel to the piece. Dimensions: Wings 58mm wide.