Rare Earth MagNet , at The MOST Powerful Permanent Magnets , compared to Ceramic's MagNet , at The Magnetic Field, strength of Rare Earth MagNet are much More Stronger. ESPECIALLY Neodymium Magnet , at The Strongest and cheapest of the type of Rare Earth MagNet, Widely Used in Electronic Motor, Linear Motor , servo motor, hard drives and MRI, Audio speaker and telecommunication. Due to the highest performance and reasonable price of Neodymium magnets, which have many applications for green technology. Such as neodymium motor magnets, it seems to be the one most commonly used in Electric car and wind energy field.