Just see a netizen asked a question about the black magnet, ask black magnet is what material, with your question, Xiao Fu here to introduce this kind of black magnet.
Black magnet, that is, a magnet with a black surface, the commonly used shapes on the market are round sheet, ring, square, with a pass, arc, semicircle, and some irregular shapes and so on.
Black rectangular neodymium magnets

Strong magnets are usually not black, but silver or gray. This is because powerful magnets are usually made of materials such as NdFeb, which are themselves silver or grey. However, some strong magnets may be painted black to increase their durability and aesthetics.
What material is black magnet?
There are many kinds of magnet materials that are black on the outside, some are originally black, some are turned black by coating, such as sintered ferrite magnets, injection ferrite magnets, black coated rare earth neodymium iron boron magnets, black epoxy bonded neodymium magnet rings, rubber magnets, etc. are all black magnets. If there are samples that can not be clearly identified, they can be sent to the magnet manufacturer for confirmation.
The above is about what kind of material the black magnet may be. If you need to buy the black magnet for the refrigerator, small black magnet, please send us an inquiry.
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