Best Answer: An alloy is a mixture of two or more metals. Brass is an alloy of Zinc and Copper. The jewlery might be nothing more than Silver plated brass. Copper itself is commonly added to Silver and Gold alloys. Lead is not used in Silver alloys or brass.Silver fillings in teeth are a Mercury/Silver alloy.est Answer: An alloy is a mixture of two or more metals. Brass is an alloy of Zinc and Copper. The jewlery might be nothing more than Silver plated brass. Copper itself is commonly added to Silver and Gold alloys. Lead is not used in Silver alloys or brass. Silver fillings in teeth are a Mercury/Silver alloy.