A certain type of prehistoric basket has been found in only two locations, one on private property and the other on a protected archaeological site  An electron microscope was used to examine one such basket  Unless an artifact has been thoroughly cleaned, an electron microscope will detect on the artifact minerals characteristic of the soil of the site where the artifact was excavated
Yet no minerals characteristic of the soil of the protected site were detected on the basket, although the basket was still encrusted with soil from the site from which it had been excavated
No minerals characteristic of the soil of the private site were detected on the basket.