Indian artifact

[railman44]

My wife's grandfather was a game warden in the early '30's.  He would pick up Indian artifacts from stream beds or wherever he'd find them.  What I'm curious about concerns a rock (which fits perfectly in the palm) that contains a hollowed out section with another rock I'm guessing used for grinding (mortar & pestle type of rig).  From where he lived, I'm assuming this probably was used by the Pawnee tribe.  Without a doubt it was made by humans.  Aside from the stone axe heads and such this aroused my interest.  I'm quite certain this is rare but is there any interest in such items?  In my minds eye I can visualize the Indians using this to smash berries or plants to use the juice or extract as war paint or herbal remedies.  Please pardon the rotten photo.

[cogar]

As an example:

0803-0198 A NATIVE AMERICAN ARTIFACT, a fine example of stone mortar and pestle, the mortar measuring 12 in. by 10 in. and 4 1/2 in. tall together with pestle, length 6 in. Collected from near the Columbia River at what is now Camas, Washington. 
http://www.ogallerie.com/auctions/2003-08/index_5.shtml

[railman44]

Thanks Cogar.  Looking at what some of the sale items brought back in 2003, I wish I would have at that event!