Remark 81.2.3. In Situation 81.2.1 if $X/B$ is good, then $X$ is integral (Spaces over Fields, Definition 71.4.1) if and only if $X$ is reduced and $|X|$ is irreducible. Moreover, for any point $\xi \in |X|$ there is a unique integral closed subspace $Z \subset X$ such that $\xi$ is the generic point of the closed subset $|Z| \subset |X|$, see Spaces over Fields, Lemma 71.4.7.

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