Gold is a soft, malleable, ductile, dense metal with a distinctive yellow color. Gold’s chemical and physical properties make it a very versatile element. Its noncorrosivenature provides protection as plating for other metals. Its malleability and ductile qualities meanit can be formed into many shapes, including very thin sheets (gold leaf) and very thin golddiode wires.

Industrial Applications and Uses

Jewelry.

When used in jewelry, gold is commonly alloyed with other metals in order to increase strength and yield colors. For instance, the alloy of gold, silver, and copper in which the amounts of silver predominates is called green gold. While the alloy of the same three elements in which copper predominates is called red gold. Finally, the alloy of gold and nickel is called white gold.

Electronics.

Owing to its relatively high electrical conductivity, low friction coefficient, and extremely high resistance to corrosion, gold metal is critically important in microelectrical circuitry, particularly in printed circuit boards, connectors, keyboard contactors, and miniaturized circuitry.

Dentistry and medicine.

Owing to its chemical inertness, its lack of toxicity, and its compatibility with all bodily fluids, gold is extensively used in dentistry in inlays, crowns, bridges, and orthodontic appliances.

Thermal barrier and IR reflectors.

Owing to its high reflective index in the far infrared region of the electromagnetic spectrum, gold is used for manufacturing radiant heating devices, thermal barriers, heat shields, and reflective coatings for solar radiation.

Mechanics.

Because of its chemical stability, gold plated on surfaces exposed to corrosive fluids or vapors is in demand for use in corrosive atmospheres.