Blauwet, who has long been interested in fossils, suspected the object was a woolly mammoth tooth, and his identification was confirmed by Tiffany Adrain, a paleontology repository instructor at the University of Iowa.
"While discovery of mammoth remains is not uncommon in Iowa, once the bones and teeth are out in the open, they can fall apart and disappear quickly because they are not completely fossilized," Adrian said in a DGR Engineering news release. "This was a lucky find."
Adrian said the tooth has likely been underground since the last glacial maximum, which is believed to have happened over 20,000 years ago.
DGR Engineering said Adrian gave officials instructions for properly preserving the waterlogged tooth, as allowing it to dry out too quickly could cause it to disintegrate.
Chis Widga, head curator at East Tennessee State University, said the 11.2-pound tooth belonged to an adult mammoth.
"This is an upper third molar, probably a right," Widga said. "Based on the degree of wear, this animal was probably in its early 30s when it died."
