The first magnet discovered was a mineral called "natural magnet," which contained iron and attracted other objects, much like magnets.
The most common magnetic minerals in various types of rock in nature are iron-titanium, iron-manganese oxides and hydroxides, iron sulfides, and iron, cobalt, nickel, and alloys. Scientists believe that the magnetic state of these minerals except iron, cobalt, nickel and their alloys is ferromagnetic, and the rest are antiferromagnetic (such as ilmenite, hematite, goethite, titanium spinel and strontium). Sulfur, etc.), or ferrite (such as magnetite, maghemite, pyrrhotite, manganese spinel, etc.). Among them, ferrite magnetite and maghemite have the strongest magnetic properties.