Gold (of indogermanisch ghel: shining, (yellow)) are a chemical element and a precious metal in such a way specified. The chemical contraction outer one for gold is derived from that latin designation Aurum.

Characteristics and characteristics

Gold consists of only a sturdy isotope and belongs thereby to the 21 pure elements. The heavy metal is soft like tin and of remarkable coloredness. It is not attacked by acids generally; an exception forms the acid mixture "for aqua regia ", a mixture from hydrochloric acid and nitric acid. In aqueous cyanide solutions gold is easily soluble under admission of oxygen as complex connection. In sour hydrothermalen solutions gold is relatively well physically soluble. The moreover one it separates easily in many metals to alloys. Some the unusual characteristics like the gold-yellow color and high ductility, can be explained after newer computations best with the relativistic effect.

Gold for thousands of years for decoration and in the form of gold coins as currency one uses. It belongs to the

Gold synthesis

Gold develops with nuclear fusion processes in Supernovae. Since center the 20. Century of human hand nuclear fusion and - initiated splitting processes (nuclear fusion respectable core fission) confirm the feasibility of the long-preserved dream of the Alchimisten. The execution of the gold synthesis is however uneconomic considering the yield and costs completely. Thus the synthesis of gold designates only a concentrating of the natural occurrences.

Gold as mineral

Gold occurs in nature as gediegenes mineral. It crystallized in the cubic crystal system, has a hardness from 2,5 to 3, a deep color, which admit accordingly as "gold yellow "are, and identical line color. In fine distribution it is depending upon grain size yellowish, ocher-brown to magenta violet and as gold magenta is then designated. With increasing temperature Feingold at chroma loses and is lightyellow glowing, before it melts. The melted metal is lemon-yellow, easily greenish and receives its intensive yellow-orange color only again if it is completely cooled down.

Admixtures of copper let appear reddish it pink or, lower the fusing temperature and increase at the same time hardness, firmness and polishing barness considerably. Rising silver portions change the color of the pure gold over lightyellow after lightgreen and finally too white; Fusing temperature and hardness change thereby only very little. Most metals, so also the well-known Platinmetalle, mercury and the iron metals lead as admixtures against it in rising portions to a decolorization in form of a rather dirty-yellow-grey to grey-white alloy. They contribute at the same time in addition, to a substantially larger hardness and firmness.

Since gold is a relatively poorly reactive element, it usually keeps its gloss and color and is easy therefore in nature to recognize. It sometimes found with quartz nationalized in Hydrothermaladern, occasionally also together with Kupfererzen. Decomposition and erosion of goldhaltiger rocks often lead to the deposit of the relatively heavy metal at the soil of flowing waters. This can lead too relatively expanded stores, which can originate from each geological age.

The component at the earth's crust is extremely small with approximately 0.01 ppm (according to 0.000001 per cent). Due to the high price, which is paid for genuine gold, the exploitation is however already worthwhile itself with relatively low gold content.

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