This beautiful plaque is a reproduction of the famous Aztec calendar, a calendar system that was used by the Aztecs as well as other Pre-Columbian peoples of central Mexico. The sun stone also called the Aztec calendar on display at the National Museum of Anthropology in Mexico City. It is one of the Mesoamerican calendars, sharing the basic structure of calendars from throughout ancient Mesoamerica. The calendar consisted of a 365 day calendar cycle called xiuhpohualli (year count) and a 260 day ritual cycle called tonalpohualli (day count). These two cycles together formed a 52 year “century,” sometimes called the “Calendar Round.” The xiuhpohualli is considered to be the agricultural calendar, since it is based on the sun, and the tonalpohualli is considered to be the sacred calendar.The calendric year began with the first appearance of the Pleiades asterism in the east immediately before the dawn light. Weight 8 Lb. Diameter 15.5″ (39cm) x Depth: 1″ (2.5cm) Item No. 441 Made of cast stone with gold finish, comes with a hole or a hook in the back for easy wall hanging. Also available in gold finish and other sizes – small, medium, and large.