leaverite
n.— «I always carry a rock hammer and a gunny sack, and when I see a likely piece of jasper or agate, I chip a corner to see how it holds up. Like as not, the whole stone may shatter making it into leaverite (leave-‘er-right there where you found it).» —by Eliot Wigginton, et al. Foxfire 5 June 1, 1979. (source: Double-Tongued Dictionary)
Further reading
Miley in The Dalles, Oregon, asks about going gunny bags meaning to “break down” or “go haywire.” Her mother uses this expression, but has no idea where she picked it up. The term gunny sack, referring to a bag made of coarse material such as jute...
Ron in Gloverville, South Carolina, wonders about the phrase since hatchet was hammer, which some use to mean “for a long period of time,” as in My family has lived here since hatchet was hammer. Another phrase he’s heard indicating the same thing...