To protect the magnet from corrosion and to strengthen the magnet material, it is usually preferable for the magnet to be coated. There are a number of options for coatings, but nickel is the most common and preferred.
Neodymium magnets are part of the Rare Earth magnet family and are the most powerful permanent magnets in the world. They are referred to as NdFeB magnets, or NIB, because they are composed of Neodymium (Nd), Iron (Fe) and Boron (B).
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