A $12 million ancient Mexican artifact has been seized in Colorado. Now the “Earth Monster” is headed back home.

The Mexican delegation stood on the tarmac Friday afternoon near Denver International Airport, waiting under hazy skies for a forklift to deliver a wooden box, the contents of which archaeologists have been searching for nearly two decades.

Inside that box — 95 inches tall, 46 inches wide, emblazoned with the Mexican flag — sat a 2,000-pound, elaborately carved stone from the ancient Olmec civilization, a precursor to the Mayans who thrived more than 2,500 years ago near the Gulf of Mexico.

The prized relic, known as Monument 9 or the Earth Monster, was carefully crafted between 800 and 400 B.C. out of volcanic rock, archaeologists believe. Its wide mouth represents the door to the underworld.

“This is one of the pieces we have been looking for for the longest time,” said Jorge Islas, Mexico’s consul general in New York.

Authorities believe the stone artifact was stolen in the late 1950s or early 1960s from the central Mexican state of Morelos. It was exhibited in New York’s famed Metropolitan Museum of Art in the 1970s, and sometime after made its way into the hands of an unnamed private collector or collectors in Colorado.

Now the stone artifact — with an estimated $12 million value — is headed back to its ancestral homeland after authorities seized it Friday, part of a long-term investigation by the Manhattan District Attorney’s Office into stolen Olmec antiquities.

“This is testimony our nation is recovering our great patrimony,” Marcelo Ebrard Casaubon, Mexico’s foreign secretary, said during a news conference.

“A decisive civilization”

Monument 9 isn’t just any old Mexican antiquity.

The Olmecs were the earliest known major Mesoamerican civilization, dominating the tropical lowland of the modern-day Mexican states of Veracruz and Tabasco south of Mexico City.

Architecture from the Olmecs is quite advanced, said Mario Córdova, an archaeologist who accompanied the Mexican delegation to Denver. That’s why it’s so valued and desired.

“It was a decisive civilization,” Casaubon said.

The Earth Monster sports iconography of jaguars, revered as the most dangerous animal in Central and South America, as well as sacred mountains and indigenous plants.

Archaeologists don’t know how much was taken from the Chalcatzingo Archaeological Zone, but the looting was significant, Córdova said. Mexican authorities believe sometime in the late 1950s or early 1960s, looters broke Monument 9 into pieces and smuggled it into the United States.

The statue first appeared in a 1968 issue of American Antiquity, an archaeology journal, Mexican authorities said.

The Met exhibited the work from July 1970 through February 1971 as part of its Before Cortes exhibition, a museum spokesperson said. The relic was on loan to the museum from the Munson-Williams-Proctor Arts Institute in Utica, NY.

Córdova and other archaeologists spent the past 18 years looking for this significant piece of Mexican history. It’s not clear when, or how, the multimillion-dollar antiquity made its way into the hands of the Colorado collectors.

Authorities didn’t divulge these individuals’ identities on Friday.

“They got a settlement,” Islas told The Denver Post. “They’re super famous, super wealthy people.”

The Mexican government approached the Manhattan District Attorney’s Office with evidence that the artifact had been stolen and authorities located it this year, said Alejandro Celorio, principal legal advisor for Mexico’s foreign ministry.

Douglas Cohen, a spokesperson for the Manhattan DA’s office, said Friday’s seizure came as part of a long-term investigation into stolen Olmec antiquities. The office sports an antiquities trafficking unit that spearheads some of the country’s largest art-crime investigations. In recent months, the team returned stolen artifacts to Iraq, China and Yemen, among other countries.

Recovering lost heritage