The mystery of the Maya volcanic ash pottery
A series of Maya pottery items dating back to the Late Classic Period have long been the source of mystery among experts due to the materials from which they were made – large quantities of volcanic ash. The mystery lies in the fact that there are not any volcanoes in eastern Central America, nor have archaeologists found evidence the Maya mined ash locally. A new study published in the journal Geology has now ruled out an enormous volcanic blast from afar as the source of the ash, but the final puzzle still remains to be solved.
Volcanic ash has long been known as the specific tempering agent, which was mixed with limestone, in the Late Classic Maya ceramics (600 – 900 AD). But how did relatively large volumes of volcanic ash become available for manufacturing of pottery? While it has been accepted that the ash was of non-local origin (the closest volcanic source is 350 km away), this anomaly has never been explained. Were the Maya opportunists when a single eruption deposited ash in their midst to exploit over several centuries? Or did a sequence of ash falls concentrate in the Late Classic promoting new ceramic production strategies?
An example of Mayan vase of the Late Classical Period. Copan, Honduras. Source: Wikipedia
The latest study, which involved the analysis of the crystal structure of the ash, has now ruled out one of the main candidates as the source – the Ilpango volcano in El Salvador, according to a report in Live Science. But this has only further deepens the mystery.
Lead author Kevin Coffey, a geology master's student at the University of California, Los Angeles, explained that the Ilopango volcano had a devastating eruption, destroying and burying nearby Mayan cities in the fifth century, but a comparison of the tiny zircon crystals within the pottery and that known to have come from the Ilopango volcano failed to provide a match. Though the researchers tested only a handful of pottery fragments, the chemical signature of the zircon crystals also differs among pots, hinting that the ash came from at least two volcanoes.
"While we're a little sad not to have solved the mystery, we're really confident we can say the most likely source quite conclusively isn't a match," said Coffey. "Every time I turn another leaf in this thing, it opens up a new problem," said study co-author Anabel Ford, director of the MesoAmerican Research Center at the University of California, Santa Barbara.
The UCLA team hopes to test more candidate volcanoes from the Pacific coast, and search for hidden ash deposits on the Yucatan Peninsula. There are 11 potential volcanoes lined up along western Central America. Analyzing more potsherds could also provide new clues to the origin of the ash, Coffey said.
"What we found was pretty surprising," Coffey told Live Science. "The mystery has gotten all the more mysterious."
Featured image: Creating pottery. Image source.