Rare earth magnets, rare earth magnet and a method of manufacturing a rotary machine

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PROBLEM TO BE SOLVED : To provide a rare earth magnet having excellent corrosion resistance.SOLUTION : A rare earth magnet 100 comprises an R-T-B based magnet element 10 containing a rare earth element R, a transition metal element T and boron B, a first protective layer 20 covering the surface of the magnet element 10, and a second protective layer 22 covering the surface of the first protective layer 20. The magnet element 10 contains Fe as T, the first protective layer 20 contains R, Fe and Al, and the second protective layer 22 contains R and Al. The ratio of the number of Fe atoms for the total number of atoms in the first protective layer 20 is higher than the ratio of the number of Fe atoms for the total number of atoms in the second protective layer 22.