It was on the top of the pyramid of Amenemhat III. Carved from a single piece of basalt c. 1850 BC
Translation of the inscriptions:
Eastern Face:
Words spoken, may the sight be open to the king of upper and lower Egypt, the lord of the two lands, Nimaatre, so he may see the lord of the horizon and his crossing of the upper sky. May it be given the appearing to the Son of Ra, Amenemhat, as a god, lord of everlasting and indestructible
Word spoken, by the sovereign, I have given the beautiful horizon, the Two Ladies (Nekhbet and Wadjet), and he who takes the inheritance of the two lands, so you may rest upon it, which pleases the sky. Word spoken by the horizon: may you rest upon it, which please the sky
Northern Face:
Word spoken, higher is the Ba of the king of upper and lower Egypt, Nimaatre, than the height of Orion as it joins the Duat. Ra-Horakhty, he makes firm, the Son of Ra, of his body, Amenemhat, who is in the midst of the northern starry sky, and Neith who is content concerning it
The living Horus, great of might, the Two Ladies (Nebty), who inherited the two lands, the golden Horus - enduring of life, the Son of Ra - Amenemhat, given life, like Ra, forever.
The living Horus, great of might, the Two Ladies, who inherited the two lands, the golden Horus, enduring of life, the king of Upper and Lower Egypt, Nimaatre, given life, like Ra, forever
Western Face
... the great one, the ribs of Osiris, lord of the Thinite nome, that are under the feet of the good god, the lord of the two lands and of doing, the son of Ra, of his body, Amenemhat. Ptah, who is south of his wall, the lord of truth and the beloved Ankhtawy (the living two lands) ...
Word spoken by Ptah, given all life, stability, power, to the good god, the golden Horus - enduring of life, Nimaatre. Words spoken by Sokar-Osiris, lord of all the living god, of ...
Southern Face
Words spoken by, Imiut/Anubis, he who has upon his mountain, and behind the king of upper and lower Egypt, the lord of doing Nimaatre, united with the western desert inside the great shrine. The lord of good offering, who is in it and given it, his inheritance. The lord of eternity and for everlasting.
Word spoken by Imuit/Anubis, I have given all places, good, pure and the spirit of the beautiful west to the king of upper and lower Egypt, the lord of the two lands, Nimaatre, commanding to him, may you rest the upon it, word spoken by the beautiful west, may you rest the upon it