Slip Sliding Away

Originally the Pyramids were sheathed in highly polished white Tura limestone casing stones. The limestone from Tura was the finest and whitest of all the Egyptian quarries. The Tura limestone was quarried from deep underground in a stone deposit South of Cairo. The miners tunneled deep underground to cut the stones out, leaving some limestone behind as pillars to support the caverns left behind. The stone casings fit together accurate to within 1/100th of an inch. All total, they were around five feet long, five feet high, and six feet deep and weighed around 15 metric tons each. Imagine the Pyramids as shining white structures rather like sunbeams.
So what happened to the beautiful casing stones? In AD 1303, a massive earthquake caused many of the outer casing stones to slide to the base of the pyramids. The stones were then carted away at the orders of Bahari Sultan An-Nasir Nasir-ad-Din al-Hasan in 1356 to build mosques and fortresses in nearby Cairo.