bronze (alloy of copper 銅|铜 and tin 錫|锡[xi1])

brass (alloy of copper 銅|铜[tong2] and zinc 鋅|锌[xin1])

gunmetal (alloy of copper, tin and zinc)

copper-nickel alloy

copper (pure copper, as opposed to alloy)

copper (chemistry); see also 銅|铜[tong2]

bronze casting

copper sulfate CuSO4

natural copper; chalcopyrite; copper iron sulfide CuFeS2