Radio carbon dating has revealed that a skull found in a Tooele attic in June belongs to an American Indian female who died in her early 20s and lived between 1620 and 1800, according to Assistant State Archaeologist Ron Rood.

The skull, which was discovered during repair work on the roof of Paul and Karen Dupaix century-old home, was sent to a lab in Florida to determine its age about a month ago.

“The dating is complicated because comparatively the skull is not as old as the things we usually carbon date, which is why the range of possible dates is so wide,” said Rood.

Radio carbon dating is based upon the decay of naturally occurring radio active carbon in humans. The testing allows researchers to discover the rate of decay, measure how much carbon is left in the human sample, and compare it to a reference point on a chart of decaying radioactive carbon levels.

Rood said it’s very likely that a skull from 1620 could still have skin attached, as this skull did.

“It all depends on how the skull was buried,” said Rood. “We live in a really dry climate which is good for preservation. There are archaeological examples with skin still attached that are several thousand years old.”

Rood said the skull itself is rare find, from an archaeological standpoint.

“It’s a very unique and interesting specimen in the fact that it still had teeth and hair attached,” said Rood. “Most skeletons don’t.”

Rood speculates the skull was originally buried in a dry cave or alcove protected from the elements to allow for such preservation.

The cause of death is still unknown, and there wasn’t any evidence of trauma to the skull, although it was missing the jaw bone, Rood said.

Experts are also still scratching their heads over the question of where the skull came from.

“We did the radio carbon dating to help with its age, but that doesn’t really tell us very much else,” Rood said. “We don’t know its provenience, and it’s hard to interpret it.”

The State Archaeology lab plans to continue to run metric measurements on the skull and enter that information into a database that will compare the shape of the skull to different Native American tribes. But even that testing isn’t the most reliable due to a “cultural overlap” of different tribes, according to Rood.

The lab will send its finished report to different Native American tribes, allowing the tribes to make claims on the skull for reburial. If the skull is not claimed, it will be placed in the state burial vault.

As for the Dupaixs, they’ve finished remodeling their house and have put it on the market, but they don’t think their unique find has hindered or helped interest from buyers.

“This has been a really cool story,” said Paul Dupaix. “I wish I knew more about where it came from. I wish I had the answers.”

Natalie Tripp: ntripp@tooeletranscript.com