Gold is an element which has the Au symbol, which comes from the word aurum in Latin (meaning gold). This element’s atomic number is 79. It’s a metal that is ductile, malleable, shiny, soft and dense. When it’s pure, gold has the color yellow bright and it comes with a luster that makes most people consider it quite attractive. It remains so in time and it doesn’t oxidize from contact with water or air. From a chemical point of view, gold is considered a transition metal and an element from group 11. Gold is a solid chemical element which isn’t very reactive and it’s often found in a native form, as grains or nuggets, part of rocks, in alluvial deposits and veins. There are also cases when it’s found as gold compound in minerals, in most cases with tellurium.

Individual acids don’t harm gold, but aqua regia is one substance which is capable of dissolving this metal. Another solution which can dissolve it is a cyanide alkaline solution, quite common in mining operations. The gold metal will also dissolve in mercury and it will form an alloy. It is not soluble in the nitric acid, even though it’s known for the fact that it dissolves base metals and silver. Thanks to this resistance, this acid can be used to test the gold presence in an item.

Gold is a metal that is quite sought after and very valuable, for investment purposes, for jewelry and coins. This metal has been a standard in monetary policies for thousands of years and only in the last few decades has the world changed to the use of paper currency that is not backed by gold.

It is estimated that during the entire history of humankind, around 165,000 tons of gold were mined.