 We really don't. It's one of the true mysteries. They were pounded out of a quarry. There's one quarry. They all came from the same granite quarry at Aswan, Egypt, in the south of Egypt. And granite is so hard that the Egyptians did not have metal that they could chisel them out with. They didn't have a metal hard enough. They only had either copper in the beginning or later bronze, which is much softer than granite.