BOONE—We have all picked up rocks from time to time, intrigued with their shape, color or size, but few of us would go to the lengths that Collins Chew employs to collect rocks.

The amateur geologist and retired Tennessee Eastman Co. chemical engineer from Kingsport, Tenn., traveled thousands of miles by vehicle and float plane to collect samples of the oldest rocks on earth, located in Canada’s Northwest Territory along the Acasta River.

Chew has donated a 39-pound, 3.9-billion-year-old Acasta gneiss specimen to Appalachian State University’s McKinney Geology Teaching Museum. Gneiss is a type of rock characterized by alternating light and dark layers, and can be comprised of the minerals feldspar, granite, quartz, muscovite, biotite and hornblende.

The specimen is on display by the main entrance to the museum in Rankin Science South.

Dr. Andrew Heckert, director of the museum, says the donation provides multiple opportunities to teach geological processes.

“It’s a special specimen,” Heckert said. “We can use this specimen to teach plate tectonics and the force required in the metamorphosis of rock and cause intrusions in it,” Heckert said. “We know about the numerical dating of similar specimens using radio-isotopic data and can teach about numerically dating rock. We can teach all of those concepts right off the bat just from this one specimen.”

Smaller samples of the Acasta gneiss will be used to study structure at the microscopic level. “This rock can tell us different stories from the atomic level to continental level,” Heckert said.

Chew’s interest in geology began with a summer job as a piper in a placer gold mine, 20 miles north of Fairbanks, Alaska, in 1951.

Chew has traveled the globe combining his lifelong love of geology with hiking. As a retiree, he says, “I do what I want to do.” He has visited every U.S. state, every Canadian province and territory, and about 25 countries spread over every continent except Africa. And, he has collected rock specimens along the way.

He collected several pounds of Acasta gneiss while on a trip to the Northwest Territory in August. Most of the specimens have been given away to various schools. “I don’t need a piece bigger than I can carry around,” he said. “I’ve given away most of it.”

Over the years, Chew has hiked the entire Appalachian Trail. He is the author of “Underfoot: A Geologic Guide to the Appalachian Trail,” which is described as a “hiker’s-eye view of the underpinnings of the mountains and valleys crossed by the Appalachian Trail, featuring pieces of almost every major geological event in Earth’s history.”

The book indexes the geology of the Appalachian Trail from start to finish, with extensive descriptions of both the rocks encountered and their context in the greater history of the planet.

He also has written “A Geologic History of Bays Mountain Park,” a state park in eastern Tennessee.