Gold

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A gold nugget, the name given to a piece of gold found in nature. This gold nugget is big.

Gold is a soft, heavy, shiny metal. It has been used for many thousands of years by people all over the world, for jewelry, decoration, and as money. Gold is important because it is rare, but also easier to use than other rare metals. It is also used to repair teeth and in electronic equipment such as computers. The color of this metal is also called gold.

Mining methods for gold are similar to other metals. Gold is so valued that the discovery of a new place to mine has sometimes caused a gold rush.

Most of the gold on Earth is deep inside the Earth's core because it is dense. Nearly all discovered gold was deposited on the surface by meteorites

Chemical properties[change | change source]

In chemistry, gold is chemical element 79, a transition metal in Group 11. It has an atomic weight of 199.96 a.m.u. Its symbol is Au, from the Latin word for gold, aurum. It is a "noble metal" meaning it has low chemical reactivity.

Gold is very soft. A goldsmith can hammer it into thin metal sheets. It is also ductile, which means it can be pulled into wire. When it is used in money or in jewelry, it is often mixed with silver or some other metal to make it harder.

Most metals are gray in color. Gold is yellow because of the way its electrons behave.[1][2] The only other metal in common use that has a non-gray color is copper.

Language and culture[change | change source]

Nancy Johnson and her Olympic gold medal

Gold can mean that something or someone is very good or has done very well. A gold medal is often the given to the first place winner in a race or other sports.

References[change | change source]

  1. "Relativity in Chemistry". Math.ucr.edu. http://math.ucr.edu/home/baez/physics/Relativity/SR/gold_color.html. Retrieved 2009-04-05.
  2. Schmidbaur, Hubert; Cronje, Stephanie; Djordjevic, Bratislav; Schuster, Oliver (2005). "Understanding gold chemistry through relativity". Chemical Physics 311 (1–2): 151–161. doi:10.1016/j.chemphys.2004.09.023 .

Other websites[change | change source]