Most Egyptian obelisks are made of red or rose granite, although some have been made of greenish black basalt and some smaller ones of sandstone.
The quarry at Aswan was used for many of them, although it continues to remain a mystery how they could have been extracted or moved from this quarry.
There is a story about an enormous granite shrine which took 2000 men three years to haul from Aswan to its place at Sais. One can't help but wonder how this could have been accomplished when the Nile River has locks today because of its varying water levels.
There are theories about how the very large pieces of granite were lifted out; they were detached from their beds with the use of fire or by wedges made of wood or iron. It has long been a belief that wooden wedges were well-driven home, and then flooded with water causing it to swell and burst the block from its bed. Recent theorists are suggesting that those wedges were made of metal which were driven into the rock in between two thin plates of metal. It's not known at all how the block was separated from the rock bed.
Theories have been presented by more than one individual about the cutting processes.
The Unfinished Obelisk at Aswan
This enormous obelisk was almost complete, but construction on it had been abandoned because it was " broken in the center. " There was a fissure or imperfection in the stone, so the lower side of it is still attached to the quarry.
It was only in the year I922 that the area around the Unfinished Obelisk was cleared by a Mr. Engelbach of the Egyptian Service of Antiquities, allowing visitors to see the obelisk. Mr. Engelbach concluded that the Aswan obelisk weighs about 1,168 tons. " . . . thought that in cutting under this lower surface supports of the native rock were at first left at regular intervals. The spaces between these supports were filled with beams of wood, and then the supports were cut away, leaving the block standing upon the beams. The holes or slots into which the wedges were driven were probably cut with chisels made of copper hardened with some alloy. The flattening of the surface of the block was, according to Mr. Engelbach, done by bruising it with a ball of 'dolorite,' which was probably held in the hand. Balls were from 5 to 22 inches in diameter, and had an average weight of I2 lb. "1
Bibliography and Footnote
Cleopatra's Needles & Other Egyptian Obelisks, E.A. Wallis Budge,
