Re: What is this unusual rock?
Marty i have to agree with John it is more than likely a mortar. Here in El Paso i have seen several of them and they all looked alot like yours. My grandfather found 7 of them on his ranch lands along with about 3 thousand arrow heads and other stone tools.Also the depression in the stone is too perfectly round for it to be a natural depression, and you can see the wear marks in it (the white rings) from the repeated use it had. If you can take it to the nearist university that has anthropology or archeolegy departments or like John said take it to a museum. the departments at either placecould posably tell you how old it is or what tribe could of made it. They could possably offer to buy it from you.
Good luck with it
From Tom - March 16, 2010 at 09:22:39