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.
Sorry...Copper oxides.