Anton Brugnams first discovered diamagnetism in 1778 while using permanent magnets in his search for materials containing iron. Magnetism takes many other forms, but except for ferromagnetism, they are usually too weak to be observed except by sensitive laboratory instruments or at very low temperatures. These include nickel, cobalt, and some rare earth metals such as samarium or neodymium, which are used to make super-strong permanent magnets. Other metals besides iron can have ferromagnetic properties. Thereafter, the magnetic compass became a tremendous aid to navigation, particularly during the day and on nights when the stars were hidden by clouds. 1000, the Chinese discovered that a magnet floating in a bowl of water always lined up in the north-south direction. People soon learned that they could magnetize an iron needle by stroking it with a lodestone, causing a majority of the unpaired electrons in the needle to line up in one direction. While scientists don't know exactly how lodestones form, "most scientists believe that lodestone is magnetite that has been hit by lightning," according to the University of Arizona. These naturally occurring magnets are called lodestones. Pieces of magnetite can be found scattered on or near the surface of the Earth, and occasionally, one will be magnetized. The prefix "ferro" refers to iron because permanent magnetism was first observed in a form of natural iron ore called magnetite, Fe3O4. Permanent magnets are the result of ferromagnetism. If the alignment of unpaired electrons persists without the application of an external magnetic field or electric current, it produces a permanent magnet. (Image credit: Aleksandr Pobedimskiy via Shutterstock) Magnetite (also known as lodestone) is the most magnetic of all the naturally-occurring minerals on Earth. When a significant majority of unpaired electrons are aligned with their spins in the same direction, they combine to produce a magnetic field that is strong enough to be observed on a macroscopic scale. The direction of their spin determines the direction of the magnetic field, according to the Non-Destructive Testing (NDT) Resource Center. However, some atoms contain one or more unpaired electrons, and these unpaired electrons create a tiny magnetic field. In this case, the magnetic fields created by those spins point in opposite directions, so they cancel each other. Electrons all have a fundamental quantum mechanical property of angular momentum, known as "spin." Inside atoms, most electrons tend to form pairs in which one of them is "spin up" and the other is "spin down," or in other words their angular momenta point in opposite directions. Magnetic fields are generated by the motion of electric charges, according to HyperPhysics.
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