Archeologist Mark Lehner, a key member of the NOVA
expedition, crouches in a granite trench that abuts one side
of the Unfinished Obelisk. Lehner holds a piece of dolerite
similar to the kind that he and others believe Egyptian
quarrymen used to pound out the trench around the edges of the
obelisk. They then lifted the pulverized granite dust out of
the trenches with baskets. Evidence also exists that workers
pounded underneath the obelisk until the monument rested on a
thin spine.
Lehner says that huge levers were probably used to snap the
obelisk from its spine, freeing it so it could be carved more
finely and transported.