Authenticity and Scholarship

The stone is an authenticated late Mexica monument; the scholarly dispute concerns iconography, not genuineness. The long-standing reading of the central face is the sun god Tonatiuh gazing out from the Ollin glyph. Other scholars argue for Tlaltecuhtli, the earth monster who swallows the sun at dusk, or for a hybrid night-sun called Yohualtecuhtli, the argument turning on features such as the clawed hands and the sacrificial imagery. The popular name Calendar Stone is likewise misleading, since the monument is not a functioning calendar but a cosmological statement that incorporates calendrical signs. The entry records the central-face identification as debated while treating the object and its date as secure.

What function the stone actually served remains debated. Leon y Gama's original reading treated it primarily as a calendrical or astronomical device, and it was displayed mounted vertically on a cathedral wall for roughly a century on that assumption. In the 1870s the archaeologist Alfredo Chavero argued instead that the stone was a cuauhxicalli or temalacatl, a sacrificial vessel or gladiatorial-sacrifice platform meant to lie horizontal rather than stand upright, its carved surface receiving offerings or blood rather than being read as an astronomical instrument. Current scholarship generally treats the stone as a cosmological and political monument encoding calendar glyphs and Mexica imperial ideology together, a synthesis of the earlier positions rather than a simple resolution of the calendar-versus-altar debate.