The faces of the four presidents on Mount Rushmore were not carved with a hammer and chisel, that much we know.
Dynamite to get the rock into rough shape, then a lot of strong men equipped with jackhammers and other industrial power tools to add the artistic contours were used.
Imagine the artist standing at a distance with a walkie talkie to give guidance:
“A little more off the left cheek, more, more, now taper it down into the chin. Taper more, taper more, Viola! A masterpiece!”