Copper and bronze would fall under Class 2 materials for adult jewelry. For purposes of complying with the law, requirements referring to metal include metal alloys, so the percentage of lead allowed in adult jewelry would depend on whether the copper or bronze is electroplated or unplated. Metallic materials used in children's jewelry must be either a Class 1 material or contain less than 0.06% lead by weight, under California law. Please note, however, that under the federal Consumer Product Safety Improvement Act (CPSIA), all children's products must currently contain less than 0.03% (300 ppm) lead by weight (this restriction will drop to 100 ppm August 14, 2011, if technically feasible). The CPSIA defines "children" as age 12 and under. DTSC strongly encourages you to check with your suppliers and obtain certificates of compliance and other detailed information about the composition of the materials you purchase from them.