There are more riddles to be discovered<p><a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Egyptian_pyramid_construction_techniques#Limestone_concrete_hypothesis" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Egyptian_pyramid_construction_...</a><p>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.