Most metals do not exist on their own. They are joined with other chemicals to make substances which do not have the properties of metals. For example, these substances do not have a shiny surface or conduct electricity. That is why an ore may contain a large amount of metal but does not have any properties of metals.

Metal ores can be made to give up their metal by being heated very strongly. They may be mixed with other materials which help the metal to escape. For example, iron is heated with coke and limestone.