Our copper is all 100% copper, it is no t mixed with metal or   iron. Our copper is all carefully hand hammered and cooked to perfection to get that color of patina that you are looking for. Unlike other copper products that come from Egypt , China, or India our copper will not turn green or start to rust , it is natural product so you do need to protect it from acetic acids (such as lime juice) to keep your patina looking its best.