Geology and the Great Sphinx

Good topic, Jon. Allied with the age of the Great Pyramid, is the problem of stone-working. Flinders Petrie was an indefatigable collector of piccies of holes, slabs, cuts and sundry workings of stone. Not just for construction of pyramids, columns, temples, but everyday objects. Some work is so intricate that lapidaries would be hard-pressed to match it today. Take diorite vases. A hard material, it was fashioned into elegant long-necked vases, hollowed out inside to form a thin shell. In one collection, archaeologists found not one or two, but around 50,000. How masses were cut and moved is still debated as very little evidence of tools used in the processes has been found. Were copper saws impregnated with gemstones used for cutting? How about large holes drilled in stone? Or the sarcophagus in the King`s Chamber of the Great Pyramid machined from one piece of granite?