The capstone itself remains unknown, and no fragment has been conclusively identified as belonging to it. Nevertheless, most Egyptologists consider it highly likely that the pyramid originally had a capstone because: - nearly all Egyptian pyramids were designed to end with a pyramidion, pyramidia have been found from several other pyramids, the geometry of the pyramid naturally implies a completed apex.

An interesting question is when we first know that the capstone was already missing. The earliest known clear description comes from the Greek historian Diodorus Siculus, who visited Egypt around 60-56 BC. He described the summit of the Great Pyramid as a small flat platform rather than a pointed apex.

The Roman writer Pliny the Elder also mentioned a flat summit in the 1st century AD.

This means that: the capstone was already missing by about 60 BC at the latest, we do not know whether it disappeared 100 years, 500 years, or even 2,000 years earlier.

In fact, if we imagine Pythagoras standing on the Giza Plateau around 500 BC, we cannot know for certain whether he saw the pyramid with its capstone still in place or already missing. Historical sources do not tell us. The only firm evidence is that about 440 years later, Diodorus recorded the summit as already flat.

This remains one of the small but intriguing mysteries of Giza: we know that a capstone was probably intended and most likely existed, yet we do not know exactly what it looked like, what material it was made from, or when it disappeared.