銀(Silver) : 化學符號Ag，原子序數47，是一種過渡金屬。銀化學性質 穩定，活躍性低，價格貴，導熱、導電性能很好，不易受化學藥品腐蝕，質軟，富延展性。其反光率極高，可達99%以上。純銀的形態主要分為銀錠(bar/ingot)與銀粒(granule)兩種。
隨著電子工業技術的發展，幾年銀逐漸被使用在電子產品中，工業需求隨電子產品成長而上升，不再只是飾品與保值之用。
A soft, white, lustrous transition metal, it possesses the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. The metal occurs naturally in its pure, free form (native silver), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a byproduct of copper, gold, lead, and zinc refining.
Silver appear in two forms: ingot/bar and granule. It is widely used in electronic industry in the last decades.
