So...tell us all what the heck this thing is, what it might be made of, and how it came to be. The first prize is the usual, a sense of smug satisfaction! Those are a couple of bedrock mortars at the base, providing some sense of scale (they are holes formed as the indigenous people of the region ground up acorns; they are 6-7 inches across). Below is a closeup of the base. The elevation is around 7,000 feet.