(CNN) -- Seattle paleontologists Friday safely removed the largest fossilized mammoth tusk discovered in the region from a construction site, according to the Burke Museum of Natural History and Culture.
The fossil is probably a tusk from a Columbian mammoth, or Mammuthus columbi, which was designated the Washington state fossil in 1998, according to a statement on the museum website.
The tusk, 8 feet 6 inches long, appears to be the most intact and largest discovered in Seattle.
The fossil was found Tuesday about 7 feet below an AMLI Residential Partners apartment development site, the statement said.
Burke paleontologists estimate that the tusk is at least 16,000 years old, but could be up to 60,000 years old. Carbon dating would provide a definitive age.
"The tusk presents a rare opportunity for paleontologists and other researchers to understand the paleoenvironmental conditions present in Seattle during the ice age," the statement said.
Scott Koppelman, senior vice president of AMLI Residential, said in a prepared statement that the excavation will cause a construction delay, "but the scientific and educational benefits of this discovery clearly outweigh the costs and delay. This is an exciting discovery for our local Northwest history."
The tusk was taken to the museum, which has paleontology collections that include 25 mammoth fossils from King County, most of which are skeletal fragments and were found in Seattle.
Burke paleontologists earlier removed dirt from around the waterlogged tusk with shovels, trowels and brushes, and placed layers of plaster-soaked burlap bandages on one side of the tusk, the museum said in a statement.
The plaster was meant to protect the tusk when moved. The drying process could take at least 12 months, during which time Burke conservators will remove the plaster and repair any damage to the tusk.
"Since the tusk is on private property, it could have ended up in a private collection," said Christian Sidor, the museum's curator of vertebrate paleontology. "We are very fortunate that AMLI contacted us to remove and care for the tusk."
According to the museum, contemporary ice age mammals include giant ground sloths (Megalonyx jeffersoni) like one found at SeaTac airport and now on display at the Burke Museum, and extinct bison (Bison antiquus), among others.
"Conditions were much colder and drier than today, and the region was probably covered with grassland and occasional pine trees, akin to the northern edges of modern boreal forests," the statement said.
Mastodons and mammoths are ancient elephant relatives that once inhabited North America, the statement said. Both became extinct as glaciers receded at the end of the ice ages between 10,000 and 11,000 years ago.
Mammoths, which were larger than mastodons and much more closely related to elephants, arrived in North America from Asia about 2 million years ago, according to the museum.
"Columbian Mammoths grew to 12 feet at the shoulder, taller than woolly mammoths (Mammuthus primigenius) and about the size of the modern Asian elephant (Elephas maximus)," the museum website said. "Their very long tusks curved down from the face, then upward at the ends. Columbian mammoths were herbivores, with a diet that included grasses and conifers. They chewed grass with large, flat, washboard-like teeth that are very similar to the teeth of modern elephants."