Various mine claims dating back to as far as the early 1950s still lay along the Parashant National Monument wilderness. Grand Canyon through hiker Rich Rudow shows what you can find if you decide to look into a claim. Thomas Hawthorne/azcentral.com

President Bill Clinton, with Interior Secretary Bruce Babbitt (from left); Arizona Congressman Ed Pastor; California Congressman Sam Farr; National Park Superintendent Alan O'Neill and Bureau of Land Management Superintendent Roger Taylor in attendance, signs a proclamation to create three new national monuments in Arizona on Jan. 11, 2000.(Photo: The Republic)

Arizona's Grand Canyon-Parashant National Monument will not be eliminated or downsized after a review by the Interior Department, Secretary Ryan Zinke announced Friday.

In a statement outlining his decision, Zinke said the monument holds "some of the most pristine and undeformed geological formations in North America, which show the scientific history of our earth while containing thousands of years of human relics and fossils.”

Trump's order grew out of a debate over a president's power to designate monuments on public lands without congressional action. Two monuments in Utah — Grand Staircase-Escalante, create by President Bill Clinton, and Bears Ears, created by President Barack Obama — were at the center of the debate and remain under review.

Three other national monuments in Arizona fit the description in Trump's order and are also still under review.

Grand Canyon-Parashant monument spans over 1 million acres north of the Grand Canyon. Clinton set aside the land in 2000 under the federal Antiquities Act.

Conservation groups feared the loss of monument status could open the land to developers or mining claims. The area around the Canyon is known to contain significant stores of uranium ore.

“Zinke is holding America’s national monuments hostage and we have no idea what the terms are,” Randi Spivak, public lands director for the Tucson-based Center for Biological Diversity, said in an emailed statement.

Some of the same groups opposed Trump's initial order to review so many national monuments, questioning whether he has the legal authority to rescind designations other presidents have made.

"The sooner this exercise concludes with the realization that no changes should be made to already-protected lands, the better," Mike Quigley, the Arizona director of the Wilderness Society, said in a statement.

The president's authority to eliminate national monuments may be "constrained," but it "has not been tested in courts," a Congressional Research Service report said, although past presidents have reduced their size.

Grijalva said the real test for the Antiquities Act will be over Bears Ears monument in Utah.

The light from sunset begins to strike a canyon in the Parashant National Monument wilderness in Mohave County.(Photo: Thomas Hawthorne/The Republic)

Roger Clark, a program director with the Grand Canyon Trust, said while he was pleased by Zinke’s decision over this monument, it was just one of many to go through the review process this year.

“We really are anxiously awaiting the decision on some of the more controversial monuments such as Bears Ears and Grand Staircase-Escalante,” he said.

In July, three Arizona Republican congressmen, Rep. Trent Franks, Rep. Andy Biggs and Rep. Paul Gosar, asked Trump to eliminate all four national monuments under review in the state.

Franks believed removing federal protections from the monument's land could boost Arizona's economy, his spokesman said in an email.

"But now that Zinke announced this monument is valuable and worth keeping, the congressman is appreciative that the department made their decision transparently and communicated it to the public in a timely fashion," the spokesman said.

Ironwood Forest National Monument, 128,917 acres, northwest of Tucson, created by Clinton in 2000.

Vermilion Cliffs National Monument, 279,568 acres, north of the Grand Canyon, created by Clinton in 2000.

Sonoran Desert National Monument, southwest of Phoenix, 486,146 acres, created by Clinton in 2001.

A fifth monument created by Clinton, the Agua Fria National Monument north of Phoenix, was too small to fall under the Trump order. It covers just over 71,000 acres.

In all, there are 18 national monuments in Arizona, the most of any state.

Environmental coverage on azcentral.com and in The Republic is supported by a grant from the Nina Mason Pulliam Charitable Trust. Follow the azcentral and Arizona Republic environmental reporting team at OurGrandAZ on Facebook, Twitter and Instagram.