What we have been taught is that the ancient Egyptians were in posession of only simple hand tools, and that the only metals available to the Egyptians of the fourth dynasty, when the Giza Pyramids were built, were copper, gold, and silver. What is inferred, therefore, is that absent the tools made from these materials, the simple abrasive experiments actually demonstrate the stone-working methods of ancient Egypt. We are told that the ancient Egyptians had not yet developed the knowledge to extract the raw materials necessary to produce iron and steel. It has been suggested that they may have used meteoric iron, because they found it lying on the ground, but they did not mine the ore and smelt it in a foundry. Support for this view is the lack of evidence that they used tools made of any material other than copper, stone, and wood. Yet absence of evidence is not evidence of absence. Although sophisticated tools made of iron or steel may not yet have been discovered in the archaeological record, what has been found is not adequate enough to explain how the artifacts were created.
Christopher Dunn Lost Technologies of Ancient Egypt: Advanced Engineering in the Temples of the Pharaohs