Deterioration of the Great Sphinx of Egypt continues to spark controversy.
The monument's noseless face is missing its upper lip as well as part of one eye. The monument is falling prey to excessive moisture, which dissolves salts. The salty solution is then drawn to the surface where it recrystallizes, undermining surface stones that eventually crumble into dust.The 4,600-year-old sphinx is made from limestone, perhaps 50 million years old. It has gone through a series of renovations, mostly unsuccessful.