Tiny stars, major shine. These dainty opal star studs are made with 18K gold vermeil and shimmer with just the right dose of celestial magic. Opals give them that dreamy glow, and the 4mm size makes them perfect for stacking or wearing solo. Finished with classic butterfly backs for comfy, all-day sparkle. Measures 4mm star shape opals. Made of 18K gold vermeil over sterling silver. Hypoallergenic and nickel-free. Butterfly backings Our goal is to make jewelry that is fun, meaningful, stylish and made of quality materials that will last. All of our earrings, rings, studs, and charms are cast in recycled sterling silver. Our gold is 18k gold vermeil (pronounced ver-may). Vermeil is a process of plating at least 2. 5 microns of gold over solid sterling silver. Our chains are all recycled sterling silver or gold filled and made in the USA. We assemble, package and ship all of our jewelry from our studio in Half Moon Bay, California. To avoid tarnishing, we recommend keeping your jewelry dry. That means avoiding contact with chlorine, soaps, lotions, perfumes, hand sanitizers, cosmetics or cleaning products. We recommend storing your pieces in a soft cloth, protected from other items in your jewelry box or tray to avoid scratching. To clean, simply dip a lint-free, soft cloth in a warm bath of mild soapy water and gently rub. After you have cleaned, simply dry with a lint-free, soft cloth.