A time traveler who makes a living as an antiquities dealer tells a tale of a Greek urn that appeared in two different places at the same time.
If the Time Traveller sold his wares directly from the maker, modern tests would show that they are only a few years old. They are stored in an underground cavern somewhere in the Pliocene to rack up the appropriate number of centuries, so that tests for thermoluminescence and cosmic ray tracks give the right answer.

Variants

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  1. “Time Out of Joint” by Pauline Ashwell, in Analog, January 2000.
    2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . written by Pauline Ashwell