In mathematical hieroglyphic texts the vertical height of a Pyramid was expressed by the word peremus.
Some Egyptologists think that permemus is the original word from which our modern word Pyramid is derived.
When the figure of a Pyramid was used as a hieroglyphic sign on the painted walls of the masabas in the period of the Great Pyramid (the IVth Dynasty of Egyptian Kings) it was capstone project writer portrayed in white with a yellow (golden) capstone and a temenos (enclosure) wall.
The reason why it was thus represented, was to show the top-stone representing the sun, both literal and symbolic (the latter symbolising Christ “the Sun of righteousness” – Malachi 4:2). It was appropriate indeed that the crowning Top-Stone of a Pyramid was regarded as a sacred one.
While ancient Egyptians, Mystics (ancient and modern) and Christians have widely different views on some matters, they are all agreed on the basic idea with regard to the symbolism of the top-stone or headstone in that it represents the Sun, literal or symbolic (Psalm 118: 22024; Zechariah 4: 6-7; Matthew 21:42; Mark 12:10; Luke 20:17; Acts 4:11).
This interpretation of the symbolism has persisted right down the centuries from the time the Great Pyramid was built till the present day. In the Egyptian Museum of Antiquities in Cairo there is exhibited the dark grey granite capstone from the Cenotaph Pyramid of Ammenemes III (XIIth Dynasty) at Dahshur. On this pyramidal top-stone the winged Sun-disc is depicted.
Egyptian Obelisks were invariably capped with a small Pyramid, which is also called a Pyramidion. In effect, an obelisk was a Pyramid capstone on a high plinth, and is so described by the American Egyptologist, Professor J. H. Breasted. Sometimes the Pyramidions of obelisks were also inscribed with a form of the Sun-God.