A modern penknife cannot mark it. From tiny patterns near the carved surfaces, Dorland determined it was first chiseled into rough form, probably using diamonds. The finer shaping, grinding and polishing, Dorland believes, was done with innumerable applications of water and silicon-crystal sand. If true, it would have taken 300 years of continuous labor. We must accept this almost unimaginable feat, or admit to the use of some form of lost technology.
Modern science is stumped to explain the skill and knowledge incorporated.
It would not be a question of skill, patience and time. It would simply be impossible. As one crystallographer from Hewlitt-Packard said, The damned thing shouldn't be. The Museum of Natural History in London displays an early Paleolithic skull, dated at 38,000 years old, and excavated in 1921 in modern Zambia. On the left side of the skull is a perfectly round hole nearly a third of an inch in diameter.