Ancient Egyptians discovered the natural occurrence of mineral resources in their environment and developed methods for mining them over the course of their civilization. Recovered Egyptian texts and the excavation of mining sites demonstrate how mineral deposits, stone and various metals were all excavated and processed with increasingly sophisticated techniques for use in ancient Egyptian society.
Minerals and Rock
Natron is a naturally occurring sodium bicarbonate harvested from dried lake beds, and used by the ancient Egyptians as a desiccant in the mummification process. Alum is another substance procured from oases in the Western Desert and used to dye cloth. The remarkable pyramid and temple construction throughout the pharaonic era was made possible by quarries of extracted limestone, granite and sandstone, supplanting older, less permanent building methods that relied on mud brick.
Ancient Egyptians began mining for gold in predynastic times using open pits and performing minimal underground excavation. Green malachite often leached from potential mining sites, and the visible stains of such mineral deposits served as a guide for ancient Egyptian prospectors. Gold fragments were removed from the surrounding quartz via huge stone hammers. Hammer shapes grew more sophisticated in the Old and Middle Kingdom periods, and there is evidence of hydro-metallurgical techniques in use during those times. Prospecting in the central Eastern Desert intensified during the New Kingdom period, along with the introduction of new stone-milling and gold-washing techniques, with some mining sites employing hundreds of workers.
Additional Precious and Semi-Precious Metals
Copper mined in Egypt often contained natural arsenic, making it particularly hard and frequently used for everyday work. A copper pin excavated from an ancient Egyptian tomb dated at about 4000 B.C. is one of the oldest metal objects in Egypt. The ancient Egyptians also developed bronze as early as 4000 B.C., a direct result of recognizing how arsenic or tin strengthened copper during the smelting process. There is no direct evidence of the ancient Egyptians mining silver, and iron was known as the "metal of heaven," as they only knew it from meteoric sources until around 500 B.C.
Quarry and Mine Considerations
Granite quarries were located near the ancient Egyptian city of Aswan, while white limestone was mined from the Tura quarries south of Cairo. These high-quality grades of stone were shipped down the river for use in pyramid construction. Other quarry locations were typically located along the Nile River, as the river's course revealed sections of stone ideal for cutting. Some quarries were located as close to building sites as possible for ease of construction, such as the Giza quarries on the Giza plateau. Principle sites for copper, gold and iron mining were located in the Eastern Desert and the Sinai Peninsula.