North Dakota officials and the State Historical Society recently reached a $3 million deal to keep a rare mummified dinosaur fossil on display in the North Dakota Heritage Center, serving as the cornerstone for the facility’s $51 million expansion.

According to Phys.org, the 67 million-year-old Edmontosaurus, a duckbilled fossilized dinosaur nicknamed Dakota, had been on loan to the heritage center until July 2015. Dakota’s body weighs in at 8,500 pounds (3,855 kilograms) and totals approximately 10,000 pounds (4,535 kilograms) when including the tail and an arm, all fossilized into stone.

“They have been offered other places that wanted it, so we feel honored that they would consider keeping it here,” said Historical Society Director Merl Paaverud, according to the Jamestown Sun. He called the agreement with the Marmarth Research Foundation the “opportunity of a lifetime.”

Paaverud also indicated that the new deal allows the state to pursue fundraising from private sources, but the $3 million must be raised within the next four years.

ABC News reports that the fossilized skin of Dakota was found by high school student Tyler Lyson in 1999 on his uncle’s ranch in southwestern North Dakota. In April, Lyson said that the money received from the fossil would be used to launch the Marmarth Research Foundation endowment fund “to be used to further vertebrate paleontology.” He also stated that money would be used to “fund public digs, build up research collections, train students and further the advancement of paleontology.”

Dakota is one of a few mummified dinosaurs in existence, also having the most well preserved skin in addition to ligaments, tendons, and possibly internal organs. “Keeping Dakota here is huge — a big deal,” said Paaverud.

The grand opening of the museum on the state Capitol grounds is scheduled for Nov. 2, the 125th anniversary of North Dakota statehood.