New finds seem to imply they had iron tools as well as copper. That and organizational skills. Religious zeal could be a factor as well. Didn’t use slaves—paid workers. For labor on the project they got Meat to eat and all the beer they wanted, tax relief and—the big kicker—eternal life in the world to come. Both men and women were used to keep this thing going. They had a sort of Pizza (sans Tomato Sauce) with cheese, onions, meat. The crew also got the best medical care in the ancient world! There was an unintended benefits. By accident they invented nationalism. The workers started to see themselves as Egyptians rather than members of a village.
New finds seem to imply they had iron tools as well as copper.
As a blacksmith, it’s my theory that they knew how to
make copper tools that were much longer wearing and harder
than as surmised. Iron oxides can be considerably harder
than pure copper, up to 3 times the Mohs number.
Remember it is what these people worked with every day
and so a tool maker could have realized this and put it
to good use.
A tool maker who could make a tool that would last twice
or three times as long and cut better would have been
rewarded for it.