Silver can be found in the form of one of its ores, such as chlorargyrite or galena, in the silver deposits of countries including Chile, Bolivia and Peru. Silver may be naturally found in its native, unreactive state in the form of nuggets, although this occurrence is extremely rare.
Silver is often found in conjunction with other precious and semi-precious metals, such as copper and gold. The principal sources of silver in the world, as of 2015, include the copper, copper-nickel, gold, lead and zinc mines of Australia, Mexico, China, Peru, Russia and Mexico.
The silver ore is excavated using mechanical mining or explosives. The mixture of ore and rock is crushed down to reduce its size. The ore is then separated from the rubble using flotation separation, where the ore is made to float or sink relative to the rubble using surfactants. This ore is extracted and concentrated using physicochemical methods, such as smelting and chemical leaching.
Many ores are mercury-soluble, enabling their extraction through amalgamation. The technique is rarely used as of 2015, due to environmental concerns. The extracted ore is dissolved into a solution, which enables the electrolytic extraction of pure silver. The electrolytic extraction and refining of copper and lead also yield minute amounts of silver.