Semi precious stone of the red chalcedony variety (a type of micrcrystallised quartz). This stone with an ancient tradition was a symbol of life in Pharaonic Egypt. It also adorns the precious funerary pectoral of Tutankhamon. 

Cornelian is found in nature as nodules. The most ancient deposits, exploited by the Romans, are in Arabia and India. Presently cornelian is extracted in Brazil.