When metals are discovered in nature they are not generally found as a pure metal, but as part of a compound. This is because, over a very long period of time, the metal has reacted with oxygen in the air and reacted with water.
When metals are found in this state they are called ores.
An example of an ore containing copper
The less reactive metals, such as gold and platinum, are found as a pure metal, because they are very unreactive. All other metals have to be removed from their ores
Panning for gold.
Unreactive metals are easily removed from their ores. However, the more reactive the metal the more difficult it is to remove.
Shown below is a table of what process must be undertaken to remove metals from their ores:
The unreactive metals are removed form their ores simply by heating. Metals such as zinc, nickel, tin, lead and copper need to be heated with carbon (or carbon monoxide) to extract them. The more reactive metals require electrolysis (a techinique involving electricity) to achieve this. Iron, however, is removed in a blast furnace, like the one below: