Metate identification

[mrc]

Found this at an old camp location on the river. I've never seen one shaped like this and was wondering is it wore this much, or was it use for medicine or paint grinding. The end has what appears to be black staining on it and the rest has some reddish splotches that may be stains or just coloring of the stone it's hard to tell. It is wore as smooth as glass.

[mrc]

#2

[mrc]

#3

[Sharecropper]

Indian kidney stone . .

[Roy D Mercer]

First pic looks like a fire starter