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In one embodiment, a permanent magnet includes a magnet main body and a surface portion provided on a surface of the magnet main body. The magnet main body has a composition expressed by a composition formula 1 : R(Fep1Mq1Cur1Co1-p1-q1-r1)z1. The surface portion has a composition expressed by a composition formula 2 : R(Fep2Mq2Cur2Co1-p2-q2-r2)z2. In the composition formulas 1 and 2, R is at least one element selected from rare earth elements, M is at least one element selected from Ti, Zr and Hf, p1 and p2 are 0.25 to 0.45, q1 and q2 are 0.01 to 0.05, r1 and r2 are 0.01 to 0.1, z1 is 6 to 9, and z2 satisfies 0.8≦z2/z1≦0.995.