Silver Whitby Jet Marcasite Garnet Pearl Butterfly Brooch. M334. This stunning butterfly brooch is handmade in sterling silver and features a beautifully hand carved marquise shaped Whitby Jet gemstone, sourced directly from the North East coast of Yorkshire. The intricately patterned silver wings are accented with sparkling Marcasite gemstones. This exquisite and eye catching piece is also set with a deep red Garnet and Pearl gemstones. It is an exquisite and detailed piece which would make a beautiful gift. All our Whitby Jet jewellery is designed and crafted within our very own workshops in Derbyshire where a team of skilled craftsmen turn the raw Whitby Jet into these stunning pieces of jewellery. You can find other matching Whitby Jet jewellery on our website. Silver Whitby Jet Marcasite Garnet Pearl Butterfly Brooch. 38mm x 48mm, Whitby Jet; 14mm x 5mm.