Moonstone For Nourishment. Vibrant, unique and full of style, our iconic Siren collection brings semi-precious gemstones to life for a fresh everyday look. These delicate Siren Mini Nugget Hoop earrings each feature one organic shaped rose cut Moonstone gemstone set in 18kt Gold Vermeil on Sterling Silver. Each earring measures 7mm in width and 21mm in height. Every hand-crafted Monica Vinader piece comes with a 5-Year Warranty and lifetime repair service.