Masks such as this one are found in tombs, where they were placed on the chest of the deceased, perhaps as a symbolic protective device. This particular mask is made of faience, which is a man-made material consisting of powdered quartz that has been fused by heating. Both eyes on this mask were originally inlaid with bitumen, a tar-like substance found throughout the Middle East.
Frankfort, H. and H.A., John A. Wilson, and Thorkild Jacobsen. Before Philosophy: The Intellectual Adventure of Ancient Man. Baltimore: Penguin Books, 1946.
Moss, Carol. Science in Ancient Mesopotamia. New York: Franklin Watts, 1989.
Roaf, Michael. Cultural Atlas of Mesopotamia and the Ancient Near East. New York: Facts on File, 1990.