Aztec stone
[Representative Image] Mexican archeologists have found a massive stone icon that may be the most important Aztec figure ever discovered, unearthing the door to as yet unknown chambers at a ruined temple in the throbbing heart of Mexico City.Reuters

Archaeologists have unearthed a 1,000-year-old Aztec stone shrine in a pond on the side of a volcano in a city in Mexico which they believe depicts the ancient civilisation's concept of the universe, according to the Associated Press.

The stone "tetzacualco" was discovered at the centre of a natural pond below the Iztaccihuatl volcano at an elevation of nearly 13,000 feet, Mexico's National Institute of Anthropology and History (INAH) said.

The stone shrine was found along with ceramic fragments, lithic materials, lapidaries and organic remains that were associated with Tlaloc — the Aztec god of rain, lightning and thunder.

"The existence of a tetzacualco in the middle of a natural pond and the optical effect that occurs when the water mirrors, from which it seems that the structure emanates, suggests that the place is the representation of a primeval time and space, a miniature model of the universe," the INAH said in a statement.

Iris del Rocio Hernandez Bautista, an archaeologist on the project, was quoted by AP as saying that according to Mesoamerican creation myths the world had water and Cipactli (the monster of the earth) floated on the primitive waters and from his body, the sky and the earth were created.

According to her, water from the nearby springs looked like that it got diverted to the site to make an illusion that the structure and mounds of stones were floating.

"These visual effects, in addition to the characteristics of the elements that make up the site and the relationship they have with each other, make us suppose that Nahualac could represent a microcosm that evokes the primitive waters and the beginning of the mythical time-space," Bautista said.

The Nahualac site consists of two areas — the first and the main being the pond and tetzacualco.

"You can see the corners and the spurts of the walls, as well as some mounds of stones that surround it," Bautista said.

And the second area is located around 150 metres southeast of the structure, over a wide valley. Researchers also discovered ceramic pieces with decorative elements related to Tlaloc.

"In this area, ceramic materials were identified on the surface, some of them identified as Coyotlatelco (750-900 AD), Mazapa (850-900 AD) and Tollan Complex (900-1150 AD). Altogether, the archaeological evidence covers an approximate area of 300 by 100 metres," Bautista added.