Facts about Gold:
Gold, like no other metal, has a fascinating history and a special place in the world. For thousands of years it has been used as an ornament of kings, a currency and standard for global currencies, and more recently, in a wide range of electronic devices and medical applications.
Gold's many unique properties have secured it a central role in history and human development. Gold is a remarkable, rare metal, with an unparalleled combination of chemical and physical properties. It is the only yellow metal and bears its name from the Old English word for yellow, 'geolu'. It is also the only metal that forms no oxide film on it's surface in air at normal temperatures, meaning that it will never rust or tarnish.
Gold's chemical symbol, Au, comes from the latin word for gold, aurum. In the Periodic Table of Elements, gold is classified as a transitional metal with the following characteristics;
Symbol: Au
Atomic number: 79
Atomic mass: 196.96655 amu
Number of protons/electrons: 79
Number of neutrons: 118
Melting point: 1,064.43°C (1,337.58°K, 1,947.97°F)
Boiling point: 2,807.0°C (3,80.15°K, 5,084.6°F)
Density @ 293°K: 19.32 grams per cubic centimeter
Crystal structure: cubic
Gold may be alloyed with various other metals to give it special properties. In its pure form, gold has a metallic luster and is sun yellow, but when mixed or alloyed with other metals, such as silver (Ag), copper (Cu), zinc (Zn), nickel (Ni), platinum (Pt), palladium (Pd), tellurium (Te), and iron (Fe), creates various color hues ranging from silver-white to green and orange-red. Usually, red, yellow and green golds are made by adding varying amounts of copper (Cu) and silver (Ag) to produce alloys of 10 to 14 carats. White golds have traditionally been made by alloying nickel (Ni), zinc (Zn) and copper (Cu) with gold, but more recently silver (Ag) and palladium (Pd) have replaced the zinc. These color variation treatments to gold are mostly used in jewellery.
Posted on 3/26/2008 2:07:27 AM