A hearth or oven-like structure was found in front of the urns. Archaeologists believe it may have been used to:

In 1898, archaeologist Marshall Saville discovered a tomb built by the Zapotec people of Mexico. Not far from the tombs, he found a row of five clay urns, decorated with elaborate masks and jewelry. They had been created to honor a noble, or a person of the highest class. The urns were then placed as an offering in the noble's tomb. Saville brought two of the urns back to the American Museum of Natural History.
A hearth or oven-like structure was found in front of the urns. Archaeologists believe it may have been used to:
burn a ceremonial fire
fire or bake the clay urns
bake pizza
Archaeologists believe the hearth may have been used to fire the urns, which were made of ceramic, or baked clay. The base, or human figure, was made as one piece, and then the decorative details were added separately.
The masks made of clay used to decorate the face of the urn depict the Zapotec ruler.
Four of the five urns were figures wearing masks of Cociyo, the god of lightning. Cociyo was an important Zapotec deity.
The urn's cape, headdress, and earrings were clues to the identity of the noble buried in the tomb.
Archaeologists knew the urn was made for a noble because of its fancy cape, headdress, and large earrings. Only Zapotec nobles were allowed to wear accessories.
Age: found in a tomb that dates between A.D. 500-1000
Made by: the ancient Zapotec people of Mexico
Where it was discovered: in Xoxocotlan, a village in the Valley of Oaxaca, Mexico
Discovered by: Dr. Marshall Saville, the first curator of Mexican archaeology at the American Museum of Natural History