HOW DID THE ANCIENT EGYPTIANS CORE DRILL THE HARDEST OF STONE? Abstract: We know from the archeological record that the ancient Egypans could core drill the hardest of natural stone. Previously, the tool to core drill, the core drill bit, has never been idenfied. The absence of the tool has led to a range of speculaon as to how this process was accomplished. Now a core drill bit has been idenfied in a private collecon, which allows definive answers as to how it was done. This arcle analyzes the major design features of the bit. Finally, a proof of the analysis is shown by the tool marks leſt in the boom of “blind” holes, core drilled in a Kohl jar, and a stone fragment from Amarna. Today, core drilling hard stone such as granite, with modern tools and equipment, remains a difficult operaon. Lacking modern technology, how did the ancient Egypans accomplish this task? Core drilled holes, and the associated stone cores, have been widely found in the archaeological record of ancient Egypt. However, no core drill bit has ever been previously idenfied, leaving the analysis of the methodology mostly confined to the tool marks leſt behind. The typical tool marks are striaons on the exterior wall of the core, and the interior wall of the hole. The sll outstanding ancient technological quesons to be answered are: 1) What “teeth,” of sufficient hardness to cut stone, were employed? and 2) How were the “teeth” aached to the drill? Only an actual core drill bit can definively answer these quesons. The photograph below is an example of ancient Egypan core drilling in stone. Petrie Museum, University College London, UC 44993, arfact cut in half to illustrate process