[Seruzawa]

Regardless of the jokes one can see that rotary tools were used on many relics. Some are are level as modern truing tables. Such work cannot be done with stone chisels.

[Openurmind]

Absolutely.

[TXnMA]

"Such work cannot be done with stone chisels."

Such work can be done by pecking to near-net shape with a slightly harder stone -- then planing by abrading with a similar stone, with quartz sand as an abrasive -- to smooth and flatten the surface, while removing the micro-fractured surface from the pecking..

Native Americans made many finely-finished ground stone artifacts that way.