Originally Posted by mariusgmioc
Can you please substantiate the asertion that Tutankhamon's blade was differentially hardened?
I can only judge by the pictures, I never had King Tuts dagger in my hands.
But almost every picture of this particular dagger shows a brighter area around the edges, which is normally a sign for a complex heat treatment.
King Tuts dagger is fully polished, your examples only have a grinded/polished cutting edge, typical for Africa. The upper curved blades are artificially blackened.
To be 100% sure, I need to polish and etch this dagger
My personal theory is very simple. I believe, that there was a unknown sophisticated culture like the fictional Atlantis, which brought the knowledge to Egypt and other parts of the world.