Frist Stone

The Frist Stone is not a stone at all, but a mythical metallic object that, by definition, cannot ever exist.

According to SlabLegend, the Frist Stone could only be forged by a perfect who had never made an error and was incapable of ever doing so. Hence the expressions;

• "Let he who be without sin cast the frist stone."
• "As likely as tripping over a frist stone."