... manufacturing process, we can use the following materials: brass, copper, iron, aluminum. 2). Die cast (injection die cast) For this ... we can use the materials: iron, brass, zinc alloy, aluminum, copper. 5). Soft PVC (soft PVC material is only used for ... with gold, silver, nickel, rhodium, brass, copper, antique gold, antique silver, antique brass, antique copper, etc. 3). Imitation hard enamel --- ...