Rare earth magnets are strong permanent magnets. Rare earth magnets are made from alloys of rare earth elements. Rare earth magnets are much stronger than alnico or ferrite magnets, and the magnetic field produced by rare earth magnets can exceed 1200 milliteslas. Ceramic and ferrite magnets produce a field of 50 to 100 milliteslas, and are not as strong as rare earth magnets. Because rare earth magnets are very brittle, they are sometimes coated in nickel, to make them more durable and protect them from chipping and breaking. Some common applications for rare earth magnets can include, Audio speakers, fishing reel brakes, bicycle dynamos and computer hard drives.