The Properties of Gold, Silver & Copper

Gold, silver and copper are popular metals that are used for a variety of purposes in industries ranging from jewelry production to electronics manufacturing. These metals are typically sourced from large mining operations in Africa and Asia, then exported to the rest of the world for commercial and industrial use.

Gold is a radiant yellow color when found in mass, but can turn to colors including ruby, black and purple when divided into smaller fragments. Gold is the most malleable of metals, with a single gram capable of being beaten out to as wide a range as 300 feet. It is also an effective conductor of electricity and heat and does not deteriorate when in contact with air or other reagents. The most recurrent compounds found in gold include chlorauric acid and auric chloride. According to the Lenntech Water Treatments website, the use of gold dates back to around 3000 B.C.E. Gold's atomic number is 79; it has a melting point of 1062 degrees Celsius and a boiling point of around 2000 degrees.

Silver has a radiant white metallic color and is slightly harder and more resilient than gold. It is resistant to the effects of water and air, but can be damaged through contact with hydrogen sulphide or air that contains sulphur; this is why silver objects need to be cleaned and polished regularly to retain their luster. Silver is the most conductive metal in terms of heat and electricity, with a melting point of 962 degrees Celsius and a boiling point of 2212 degrees. Despite its electrical conductivity, silver’s high cost has prevented if from being used for commercial purposes. Silver has been used since ancient times and is usually monovalent, meaning it only contains one kind of compound in its structure

Copper is a highly malleable metal that can be shaped and bent without breaking when either cold or hot. Copper has been used for thousands of years, and is a very ductile metal, meaning it can be stretched out to form thin wire. Copper comes in a reddish color, is usually crystalline in structure and belongs to the "Ib" category of the periodic table, with silver and gold. Copper reacts when in contact with moist air, causing a green film to form on its surface; this coating shields the metal from damage. Copper is bettered only by silver in its electrical conductivity, but is also too expensive to be used in industry. Copper is an effective heat conductor, with a melting point of 1084 degrees.

Gold is most often used in bullion, the production of jewelry (which accounts for around 75 percent of mined gold) and for minor electrical components in various devices. Metallic gold is also sometimes applied to large building windows as a thin film to help deflect the heat of the sun’s rays. In the electronics industry, gold is used in electroplating to shield copper components from harm.

Silver is also widely used in the production of jewelry, as well as in photography. Silver contains halide salts, including silver nitrate, which are used in photographic development. Silver is also used as a decorative framing for mirrors and for the production of luxury cutlery items. The electronics industry also uses silver-based paints to shield printed circuits from harm.

Copper is used extensively in the production of electrical equipment as well as in construction, plumbing and roofing. Alloys of copper, such as copper-tin-zinc, are also used in the production of cannons and guns, accounting for its slang name “gun metal.” Copper is also used in the production of cooking wares and refrigerators -- due to its conductive qualities -- and in metal wiring.