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Ζῆν οὐκ ἄξιος, ὅτῳ μηδὲ εἷς ἐστι χρηστὸς φίλος → Life is not worth living if you do not have at least one friend.
ĕristălis: is, f.,I an unknown precious stone, Plin. 37, 10, 58, § 160 (dub.—Jan. erythallis).