Sister necklace is made of environment-friendly copper.Necklace measures approximately 18 inches. This length works on practically anyone! This necklace will not turn your skin green, red, or itchy - it's the real deal using environment-friendly copper from a very reputable copper supplier. The chain is dainty but strong, and will not break on you. We will always replace it for you if needed. Great quality to last a lifetime. A sweet, stylish accessory that shows you care.