This method involves the use of heat to extract metals from their ores. The most common pyrometallurgical processes are:

* Smelting: This is the most common method of extracting metals from ores. In smelting, the ore is heated in a furnace until the metal melts and separates from the impurities.

* Roasting: This process is used to remove impurities from ores by heating them in air. The impurities are oxidized and turned into gases, which are then released into the atmosphere.

* Refining: This process is used to further purify metals after they have been smelted. Refining involves heating the metal in the presence of a flux, which removes any remaining impurities.

2. Hydrometallurgy

This method involves the use of aqueous solutions to extract metals from their ores. The most common hydrometallurgical processes are:

* Leaching: This process involves dissolving the metal from the ore using a solvent. The solvent is typically a weak acid or a salt solution.

* Precipitation: This process involves causing the metal to precipitate out of the solution by adding a reagent. The reagent is typically a base or a reducing agent.

* Electrorefining: This process involves electrolytically depositing the metal onto a cathode. The metal is dissolved in a solution, and an electric current is passed through the solution. The metal ions in the solution are attracted to the cathode, where they are deposited.