The historical importance of the Palermo Stone has long been overshadowed by the famous Rosetta Stone, but Jill Kamil says it is now being reconsidered as a legitimate historical record of ancient Egypt The so-called Palermo Stone is the largest and best preserved fragment of a rectangular slab of basalt known as the Royal Annals of ancient Egypt's Old Kingdom. Its origin is unknown, but it may have come from a temple or another important building.