When the Egyptian alchemists developed glassmaking during the New Kingdom, it was to carry on the old religious tradition of making synthetic stones. - Joseph Davidovits

[T]here is one theory that is never taught by Egyptology, but which is obvious. I call it Theorem Number One. The stone has a religious meaning. Stone is used only for tombs, pyramids and temples. Stone is never used for secular constructions, never for palaces, garrison, houses that are made out of wood, clay, brick, never in stone, except during the Greek period... and during the Roman occupation. So never, during the genuine Egyptian civilization, was the use of stone permitted for secular constructions.

[T]he priests of had long been adept at the art of making extraordinary cements. Cement found in... the Great Pyramid... is still in good condition. This ancient mortar is far superior to cements used in construction today. The modern used to repair ancient Egyptian monuments has cracked and degraded...

[F]or god in the creation, he carves mankind and the other gods in his body, the mountain. The creation is the divine incarnation in carved stone.