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Magnets can be natural and artificial. The Earth, for example, contains magnetic substances in its nucleus. These substances, which are also in our body, make our planet a big natural magnet. That’s why when you hang a bar magnet from a thread in a horizontal position, its north pole points to the geographic north pole of the Earth. A bar magnet is an artificial magnet. This type of magnets are usually made from a combination of elements that contain iron, cobalt or nickel.
Elements
The Earth
Substances
Magnets