When heated to high temperatures magnetite loses its natural magnetism. Not all iron deposits are magnetic, however, which for many years posed a question. Recently an interesting theory has emerged concerning an anaerobic bacterium, GS-15, which has been shown to convert ferric oxide into magnetite. It is thought that GS-15, could be responsible for the creation of magnetite layers in many iron formations. Like poles repel and unlike poles attract.
Lines of force are three-dimensional, surrounding a bar magnet on all sides.
When opposite poles of a magnet are brought together, the lines of force join up and the magnets pull together. When like poles of a magnet are brought together, the lines of force push away from each other and the magnets repel each other. The north and south ends of the Earth are called the north and south poles. The ends of a magnet are called north and south poles. This is because the north pole of a magnet is north-seeking i.e. it always points to the magnetic north pole, which is close to the geographic north pole.