The Sphinx of Giza
By: Cami Sides
Background:
The Great Sphinx is believed to have been constructed during the reign of Pharaoh Khafre, somewhere around 2500 B.C., although no one knows the true origin. Most of the information in this brochure are merely estimation, assumption, and theories.
The Great Sphinx: What's it made out of?
The Sphinx of Giza is one of the most famous landmarks in Egypt, with its construction dating back to around 2500 B.C. It is carved out of limestone, which the Egyptians called the "white stone."
Fun Facts:
- Before 1905, the majority of the Sphinx's body had been covered with sand. People uncovered it to reveal its whole body for the first time in centuries.
- It is believed that the Sphinx's nose was shot off by the Turks (although originally it was believed to have been taken by Napoleon's men.)
- There are no drawings, writings, or any form of inscriptions on the Sphinx.
- To this day, no one knows the exact history of the Sphinx; most dates and historical background information is all just estimation and assumption.
Erosion
Because the sphinx had been covered by sand for centuries, it had not endured much wind erosion (except for the head, which has since had cement repairs). However, distant past Egypt is said to have had some massive flooding, which caused a lot of the body to erode.
Type of Rock:
The Great Sphinx of Giza is made out of limestone which was taken from the Giza Plateau, which is known as the Mokkatam Formation. Thousands of years ago, the area in which the Sphinx now lies was covered by a sea. As the sea retreated, it left a build up of limestone deposits, which is what the ancient Egyptians used to construct this massive monument.
Restoration and Preservation
The Sphinx has undergone extensive repairs in the 1920s and the 1980s, using cement and gypsum mortar. Sewage was being dumped in a nearby canal, and many people were concerned about polluting the Sphinx and groundwater disintegrating it. The water table is 15 feet below the Sphinx, which raises long term threats. The Great Sphinx is always under watch for erosion.
The Great Sphinx Is Now Composed Of:
Cement
Cement is a mixture of limestone and clay, which is heated and then ground into a fine powder. When mixed with water, it hardens into concrete.
Gypsum Mortar
Gypsum Mortar is also referred to as the plaster of Paris. It is a mixture of gypsum, water, and often times sand. It can be made to feel more plastic-like and hardens when the water within it evaporates.
Limestone
Limestone is the main type of rock that the Sphinx is made of. It is a sedimentary rock composed of mainly calcium carbonate.