Most people who have seen an image of the object pictured above think of it as the “Aztec calendar stone.” In fact it’s probably not a calendar, and is more appropriately referred to as the Aztec Sun Stone. It was carved from basalt sometime between the early 14th century, when the Aztec civilization came to prominence in Mexico, and 1519, when Spanish conquistadors under the command of Hernan Cortes arrived. Probably it dates from the middle of this period. It’s pretty big–12 feet across and weighs 24 tons.
The Sun Stone was discovered in December 1790 under the Zocalo, the giant central square in Mexico City that faces Mexico City Cathedral. The Spanish built the cathedral on the site of the Aztecs’ great devotional pyramid in the center of Tenochtitlan, the city upon whose ruins Mexico City was constructed. The exact meaning of the figures carved on the stone is unclear to modern scholars. The leering face at the center of the circle may be Tonatiuh, the Aztec sun god, or it could be Tlaltecuhtli, a sea monster to whom human sacrifices were made. This is the basis of the hypothesis that the Sun Stone was a sacrificial altar. Although the symbols for Aztec ceremonial days do appear on the stone, this may be linked to a historical or religious reference, such as the “Five Ages” through which the Aztecs believed the Earth passed, rather than a literal calendar.
This stone is a treasure because very little of the Aztec civilization has survived to the present day, at least very little of this magnitude. The Spanish assimilation of Mexico was one of the most brutal and thorough subjugations of one nation by another in the history of the world. Although their customs seem bizarre and bloodthirsty to us in modern times, the Aztecs–they called themselves Mexica–built quite a magnificent and ingenious civilization on the lakes of central Mexico, involving causeways, floating gardens and a complicated military/clergy caste system that was the basis of one of the most unique and interesting societies that flourished in the Americas before the coming of Europeans.
The Aztec conquest is a subject of intense debate among historians, some of whom in recent times have come to challenge the idea that a tiny, lightly-armed band of Spanish conquistadors could have torn down such a mighty empire on their own. More likely what we think of as the “conquest” was more like a revolution of various Mesoamerican nations against their Aztec rulers, using the Spanish to their advantage; of course when it was over the Spanish picked up the pieces and remade Mexico in their own image, or tried to. The Sun Stone, if it is ever fully deciphered, might be able to tell us many things about the Aztecs that were lost in the cultural assimilation that followed the conquest of 1519-21.
The Aztec Sun Stone is on display in Mexico’s National Museum of Anthropology, actually not that far from where it was found.