Gold is a metal which is mined and it usually comes out as gold ore, which is in most cases mixed with some other metal when it’s extracted. It can be combined with silver and it’s called electrum, or it can be an amalgam, when it comes mixed with mercury. Gold can be found in nature as nuggets, as flakes, as fine grain in running water or alluvial deposits and even as small grains which are embedded in rock.

There are some ores where gold appears in a composition with some other elements, but they are quite rare. These ores include krennerite, nagyagite, calaverite, petzite and sylvanite.

In most cases, gold extraction in history was done with the help of gravity, using washing tables and pans to separate the gold from the rest of the materials found. Mercury amalgamation is being used in some small operations and it can help the recovery of gold. There are some situations when the gold presents itself as coarse particles in ore and in a case like this, smelting can be done with the help of a gravity concentrate, which allows the creation of gold bars. Another method used in mining is the use of cyanides, which are useful when there are fine particles of gold in the ore.

Another method is froth flotation, useful when the gold which is found in the ore is accompanied by sulfides. In cases like this, there is an additional level of processing needed to recover the gold, either through wet pressure oxidation or through roasting. After that, there is another step, where techniques of carbon adsorption and consolidation allow the gold to be finally recovered.

In some cases, the gold is found as a minor part of the deposit, with another type of concentrate and it can be mined as the by-product of the main mining operation.