Sterling Silver Blue John Marcasite Garnet Pearl House Style Butterfly Brooch. M334. 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 stunning butterfly brooch is handmade in sterling silver and features a beautifully hand carved marquise shaped Blue John gemstone, sourced directly from Treak Cliff Cavern in Castleton. The intricately patterned silver wings are accented with sparkling Marcasite gemstones. This eye catching piece is also set with a deep red Garnet and a Freshwater Pearl. Dimensions: 38mm high x 48mm wide, Blue John; 14mm x 5mm.