Unreactive metals such as Gold are found in the Earth as the metal itself but most metals are found in compounds that require chemical reactions to extract the metals.
Metals that are less reactive than carbon can be extracted from their oxides by reduction with carbon.
Metals that are more reactive than carbon such as aluminium are extracted by electrolysis of molten compounds. The large amounts of energy used in this are expensive.
Copper can be extracted from copper-rich ores by heating the ores in a furnace. (Smelting)
The copper can be purified by electrolysis. The supply of copper-rich ores is limited.
Phytomining uses plants to absorb metal compound then plants are burned to produce ash that contains metal compounds.
Bioleaching uses bacteria to produce leachate solutions that contain metal compounds.
Copper can be obtained from solutions of copper salts by electrolysis or by displacement using scrap iron.
During electrolysis positive ions move towards negative electrode.
Aluminium and titanium cannot be extracted using carbon. Current methods of extraction are expensive as there are many stages and large amounts of energy are needed.