7mm Synthetic Opal Studs Stering Silver Ball Earrings (E23614) 7mm Synthetic Opal Material - genuine 925 sterling silver. Nickel and Lead free. Conform to International, European an American legislation regarding lead, nickel and heavy metal content. Finishing - E-Coat protects the sterling silver from tarnishing for an extended period and lets the natural beauty of the sterling silver come through. Gift Box available