this strange 4500y old piece of rock known as core 7 is ancient Egyptian it was found near the Great Pyramids at the end of the 19th century by this man the British archaeologist flenders Petri it's kept here in London in the Petri Museum it's an exact cylinder and has strange lines scored into it which are perfectly spaced in fact it's one continuous line like the grooves of a record what is it it's the core that would be thrown away when a hole is drilled in this case the hole of a door pivot but this rock
is granite how could the ancient Egyptians drill into solid Granite the strongest metal tools the Egyptians had were copper and copper is quite soft so it's mindboggling to think that that is what they use to penetrate Granite the only material really strong enough to penetrate Granite well that's diamond and if the ancient Egyptians had diamond cutting technology well then history would have to be Rewritten the shape of the groove is further evidence of impossibly advanced technology it's the grooves in Petri core 7 the are the real mystery as far as we know the ancient Egyptians
only had bow drills which moved back and forth this is a reconstruction of an ancient Egyptian bow drill it makes a very distinctive back and forth line as it drills one continuous line such as that of core 7 is the mark of a modern power drill this core seems to have been drilled out of solid Granite using a rapidly rotating drill can this possibly be true a modern Diamond tipped machine like this powered by electricity makes a core just like the ancient Egyptian one this machine turns at600 revolutions per minute how on Earth could the
Egyptians drill like this nobody knows it's clearly impossible and yet they did it the evidence is carved in stone but even this isn't the end of our mystery from looking at the space between each Revolution it's possible to work out the force of the drill The Wider the space between the groove the greater the force amazingly research shows that the core was made by a drilling process with greater strength than a modern power drill what does this tell us there are no tools of that caliber that we know of is This evidence for even far
greater civilization that had those tools that we have no historical record of it remains a an unexplained mystery and it's one of the greatest
