This is VERY exciting! Archaeologists are theorising that the huge monolith which was recently discovered in the Templo mayor [as posted here] may mark the burial site of Ahuizotl, the eighth Aztec ruler (1486-1502). If indeed it marks the tomb of Ahuizotl, it would be the first ever burial site found of an Aztec ruler and one of the most important Aztec finds ever!

The monolith, which is broken into several pieces, has been dated to the year "10 Rabbit," or 1502 — the year of Ahuizotl's death, and depicts the earth god Tlaltecuhtli. The western face of the Templo Mayor where it was found is believed to have beenthe place where the Aztecs cremated their leaders and buried their ashes in funerary jars. The area was paved over even in Aztec times and was subsequently built over by houses until recently, which may go a long way towards explaining why no burial sites have been found before.

More information:
Experts say tomb may be under monolith
Mexico Aztec god carving may be emperor's headstone