Natural magnets are minerals or metals that generate a stable magnetic field without artificial inducement. They are different from artificial magnets, which are manufactured by humans. All natural magnets are permanent, although artificial magnets can be either permanent or temporary.
Many minerals found in nature are naturally magnetic. All normal matter is slightly negatively charged on its surface as a result of the presence of electrons. When these electrons move chaotically, the result is that their slight negative charge is spread out and doesn't demonstrate any clear direction. Such a field is very weak and doesn't generate a detectable magnetic attraction.
Some minerals, such as lodestone, arrange the flow of electrons in a more orderly way. As electrons flow in a general direction, they generate a magnetic field. The greater the proportion of electrons flowing in a uniform direction, the stronger the magnetic field gets.
Lodestone is one of the most efficient natural magnets. It is a black mineral that is rich in magnetite. Magnetite is rich in oxidized iron, and iron generally permits the free flow of electrons through it. This makes magnetite such a powerful magnet that in some animals, such as pigeons, it is incorporated into their brains as an aid to sensing the earth's magnetic field.