銅(Copper) : 純銅是堅韌、柔軟、富有延展性的紫紅色而有光澤的金屬，又稱為紫銅。純銅的導電性和導熱性很高，僅次於銀。為電線電纜的最主要材料，同時也可以加工成各種合金廣泛使用於各種五金產品，是人類使用最多的非鐵金屬原料。一般工業用銅多為純度99.995%的陰極電解銅板，台灣沒有出產銅，全部仰賴進口。
It is a soft, malleable and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a reddish-orange color. It is used as a conductor of heat and electricity, as a building material and as a constituent of various metal alloys.
Generally, copper cathode with 99.995% purity is used widely in industry. Taiwan do not produce copper and totally depend to import.