Neodymium magnet http://www.permanentmagnet.com/neodym... is the strongest permanent magnet in the world currently, and it is widely used in many fields. And with Nickel, Zinc, Epoxy or other coating, it has not only anti-corrosion ability, but also good-looking appearance. However, this material is hard and brittle, thus a slight impact or crash will result in chips and cracks. Therefore, to ensure flawless materials or to avoid hurting by these magnets, it should be pretty careful when assembling and using it.