There are more riddles to be discovered https://en.wikipedia.org/wiki/Egyptian_pyramid_construction_techniques#Limestone_concrete_hypothesis https://en.wikiped

There are more riddles to be discovered https://en.wikipedia.org/wiki/Egyptian_pyramid_construction_techniques#Limestone_concrete_hypothesis https://en.wikipedia.org/wiki/Egyptian_pyramid_construction_... Utilizing scanning electron microscopy, they discovered mineral compounds and air bubbles in samples of the limestone pyramid blocks that do not occur in natural limestone.