R-T-B rare earth permanent magnet

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An R-T-B system rare earth permanent magnet, which comprises at least main phase grains consisting essentially of R 2 T 14 B compounds and a grain boundary phase having a higher amount of R than the above described main phase grains, and which satisfies the following formulas : AVE ( X ) / Y = 0.8 €‰ to €‰ 1.0 ; and ( X / Y ) max / ( X / Y ) min = 2.0 €‰ to €‰ 13.0 , wherein X represents (the weight ratio of heavy rare earth elements) / (the weight ratio of all the rare earth elements) for a given number of the above described main phase grains in the above described sintered body; Y represents (the weight ratio of heavy rare earth elements) / (the weight ratio of all the rare earth elements) for the sintered body as a whole; AVE(X) represents the mean value of X obtained for the given number of the main phase grains; (X/Y) min represents the minimum value of (X/Y) obtained for the given number of the main phase grains; and (X/Y)max represents the maximum value of (X/Y) obtained for the given number of the main phase grains.