A sintered body, manufacturing method thereof, and a varistor overvoltage protection device

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PROBLEM TO BE SOLVED : To provide a calcined body or a varistor capable of stably obtaining high varistor voltage exceeding 600 V/mm.SOLUTION : Disclosed is a calcined body which contains a zinc oxide particle as a main component and further contains a spinel particle having a bismuth oxide phase, zinc, and antimony as the main component, and a rare earth-containing particle. The calcined body is excellent in a dispersed state of the rare earth-containing particle. When an arbitrary cross-section of the calcined body is divided into squares based on a unit of half the length of an average particle diameter of the zinc oxide particle, the ratio of the number of rare earth-containing particles existing at intersection points of the squares to the number of the intersection points of the squares is defined as an index of the dispersed state of the rare earth-containing particles, and this index of the dispersed state is 8% or more.