The claim that Egyptian hard-stone artifacts carry toolmarks only a powered machine could leave. The exhibits are largely Flinders Petrie’s: the groove on Core No. 7, saw cuts on the granite coffers recording overshoots and backed-out restarts, and cusps on bowl shards implying two axes of rotation. Christopher Dunn adds his own 1995 light-gap checks with a steel parallel ground flat within .0002 inch, and proposes ultrasonic machining at 19,000 to 25,000 hertz, with the quartz in the granite vibrating in sympathy (see Piezoelectric Granite). The counter-case is empirical: Denys Stocks reproduced cores, tapered holes, striated grooves and sawn faces in Aswan granite with copper and quartz sand, and measured the rates. Since 2023 the argument has moved to CT and structured-light metrology of predynastic stone vessels; the first peer-reviewed metrology of those, in npj Heritage Science (2025), reports good concentricity but poor circularity, which is what grinding produces and precision machinery does not.
Connections
Christopher Dunn · Denys Stocks · Core No. 7 · Flinders Petrie · Giza Power Plant Theory · Piezoelectric Granite · Predynastic Hard-Stone Vases · Ben van Kerkwyk