The Shabaka Stone, sometimes Shabaqo, is a relic incised with an ancient Egyptian religious text, which dates from the Twenty-fifth Dynasty of Egypt. In later years, the stone was likely used as a millstone, which damaged the hieroglyphs. This damage is accompanied by other intentional defacements, leaving the hieroglyphic inscription in poor condition.
More information: https://en.wikipedia.org/wiki/Shabaka_Stone