The Sun Stone is a monolithic disk of basalt commonly referred to as the Aztec Calendar.  It was found on September 17, 1790 next to the Plaza Mayor, in a place called Cuauhxicalco during leveling work of the Zocalo.  The dates that are on the top say that it was build in 1479 (paragraph 13-Reed, the date in which the Mexicas placed the birth of the Fifth Sun) and erected and opened in 1481. In the center of this monument we see a face surrounded by the solar disk that according to archaeologists could correspond to Tonatiuh, the Sun God of the Mexica.

Size of the Sun Stone: Diameter: 3.60 meters. Width: 122 inches. Weight: More than 24 tons.

After its discovery, the monolith stood next to the Metropolitan Cathedral in Mexico. In the late nineteenth century it was exhibited at the Archaeological Museum of La Moneda Street until 1964, when it was transferred to the Mexica Hall Museum of Anthropology and History in Mexico.

Today, the details of the Sun Stone are on the back of the following Mexican coins: - 5c with sun rays of the ring of the Quincunces -  10c .- Part of the Ring of Sacrifice -  20c .- part of the Acatl, the thirteenth day .- 50c the ring of Acceptance .- 1  part of the Ring of the Glow - 2 pesos .- part of the ring of the Day .- 5 pesos part of the Ring of Serpents .- 10 pesos Sun Stone Circle,  the god Tonatiuh with the mask of fire.