The large stone was standing out like a sore thumb, I flipped it over and it is dished out.... The smaller stone was also strange for the area but not as interesting.
Niice! Hard to tell from the pic, but it sure has potential. Is it nicely polished or show signs of use? To bad the smaller stone wasn't found beneath it.
Sure looks like a metate and mano from here but as quito said, any sign of wear on either of the pieces. I have several metates that were flipped over. One of my best was found flipped over when metal detecting . I was laying over a 1860's military shirt button.
That caught my attention when you said you flipped it over. From what we could tell in SW Oklahoma, before the horse, they were made from local materials, and these were too heavy to carry along when they moved, so they would flip them over to protect the grinding surface, and have them on site ready for use when they returned, if they ever did.
Yes ... I had a friend tell me about them being flipped over when they left camp. He told me of a place that there were over 100 of them flipped over.
So when I saw this white rock among all the dark stones and obsidian flakes, I flipped it over....and saw it was dished. The smaller stone I found maybe 20 yards away and it just seemed a good match.