Gold is one of the most popular and well-known minerals, known for its value and special properties since the earliest of time. Most of the natural Gold specimens that have been found since early times have been smelt
ed for production. Nice specimens, therefore, are regarded very highly, and are worth much more than the standard gold value. Only recently have more specimens been available to collectors, as more miner
s have been saving some of the larger pieces for the collectors market.
Gold in its natural mineral form almost always has traces of silver, and may also contain traces of copper and iron. A Gold nugget
is usually 70 to 95 percent gold, and the remainder mostly silver. The color of pure Gold is bright golden yellow, but the greater the silver content, the whiter its color is. Much of the gold mined is actually from gold ore
rather then actual Gold specimens. The ore is often brown, iron-stained rock or massive
, and usually contains only minute traces of gold. To extract the gold, the ore is crushed, then the gold is separated from the ore by various methods.
s, a popular form of Gold with collectors, are formed when erosion causes a large piece of Gold to separate from its mother rock, and then gets carried into a stream or river. The flowing water tumbles the Gold, giving it its distinct rounded shape. The Gold eventually settles at the bottom of the water, and due to its heaviness remains there. Other nuggets also get caught in the same area, forming a placer deposit
Gold is one of the heaviest minerals. When pure, it has a specific gravity
of 19.3. Due to its weight, it can be panned because the Gold sinks to the bottom. In addition, it can be easily separated from other substances due to the weight differences. Gold is also the most malleable
substance known. It can be flattened out to less than .00001 of an inch (less than .000065 cm), and a 1 oz. (28 gram) mass can stretch out to a distance of over 50 miles (75 kilometers). Gold is also one of the most resistant
metals. It won't tarnish
, discolor, crumble, or be affected by most solvent
s. This adds on to the uniqueness and allure of this mineral.
Gold is usually associated with Pyrite
and other sulfides
, and sometimes may not be noticed because of the association with these resembling minerals. In certain localities, minerals that contain these sulfides are heated high enough for the sulfides to dissolve, enabling the Gold to remain intact on the matrix
. Such Gold is known as "Roasted Gold", and is occasionally sold to collectors.For additional information, see the gemstone section on Gold.