In this March 2013 file photo, Forrest Fenn sits at home in Santa Fe, N.M. Fenn hasn’t seen anything but geese, a few bald eagles and the majesty that is northern New Mexico’s landscape as he flies in a chartered helicopter along the upper Rio Grande, looking for Randy Bilyeu, a Colorado man who went missing while searching for treasure hidden by Fenn. (Jeri Clausing/AP)

Forrest Fenn has spent a lifetime hunting treasure.

Now the millionaire art dealer is searching for something more valuable than gold coins and rare memorabilia: a human life.

That life belongs to Randy Bilyeu, a 54-year-old grandfather who disappeared into the New Mexico wilderness earlier this month after he embarked on his own treasure hunt gone awry, according to the Associated Press.

“Every time we go out and don’t find Randy it’s discouraging, but we’re not going to give up,” Fenn told the AP. “There are still places out there that I want to look.”

Family members say Bilyeu was searching for a bronze chest containing nearly $2 million in gold, jewelry and artifacts that Fenn allegedly stashed somewhere in the Rocky Mountains, according to the AP. Fenn first revealed the existence of the treasure in his clue-filled, self-published memoir, “The Thrill of the Chase.” The book captivated readers with an ambiguous, 24-line poem that hints at the booty’s whereabouts, ending with:

“So hear me all and listen good,/Your effort will be worth the cold./If you are brave and in the wood/I give you title to the gold.”

Fenn told ABC News that chest contains 265 gold coins that are “mostly American eagles and double eagles, hundreds of gold nuggets, some as large as chicken eggs, ancient Chinese carved jade figures, Pre-Columbian gold animal artifacts, lots of rubies, emeralds, sapphires, and diamonds and other things.”

Fenn told ABC affiliate KOAT that he estimates 30,000 people looked for his treasure in the summer of 2014 and he was anticipating another 50,000 last summer. Treasure hunters have ended up in “remote corners of New Mexico, Yellowstone National Park and elsewhere,” according to the AP. They share their experiences on blogs and treasure-hunting forums, where people discuss clues and attempt to deconstruct the mystery. Even Fenn has been surprised by the fervent following his treasure has inspired.

“The hope of finding the treasure is one thing, of course, but there’s a sense of adventure when you get out in the mountains and in the sunshine and the fresh air,” Fenn told the AP. “One of my motives was to get the kids off the couch and away from the game machine.”

But few people were as transfixed by the mystery as Bilyeu, who actually moved to Colorado two years ago to pursue his treasure-hunting passion more aggressively.

“He was adventurous,” his daughter, identified only as “Carissa,” told “Inside Edition.” “He liked the thrill of it. He told me that it kind of connected to him spiritually.”

“We are hoping for answers real soon,” she added. “We are hoping that he is still alive.”

Fenn has urged people to search for the treasure in the summer months, but Bilyeu was undeterred by winter. Recently, family members told “Inside Edition,” he’d begun exploring locations not mentioned in Fenn’s book, telling relatives he’d finally solved the mystery.

“He had some kind of a plan that bewilders me, quite frankly,” Fenn said.

Bilyeu spent the last few weeks of 2015 scouting a river west of Santa Fe, N.M., relatives would later tell rescuers, according to the AP. They said he’d purchased a raft before departing on Jan. 5, bringing with him a GPS device, a wet suit, waders and his dog, Leo, according to the AP.

Bilyeu’s car was discovered outside Santa Fe, according to Yahoo News. Inside the vehicle, rescuers found “boots, water, a Thermos, and dog food,” Yahoo reported.

The adventurer also left maps in his car and a sandwich, leading some to believe he planned to return to the car shortly thereafter, the AP reported.

When he wasn’t heard from, Bilyeu’s ex-wife filed a missing person’s report on Jan. 14, according to the AP. The treasure hunter’s raft was found the next day, as well Leo, who was alive.

Rescuers from the New Mexico Search and Rescue team and the state police spent several days exploring the area on foot and from the air, but there’s been no trace of Bilyeu, the AP reported.

“Unfortunately, we just don’t have anything to go on right now,” State Police spokeswoman Sgt. Elizabeth Armijo told the AP. “If someone were to find clothing or footprints or just something that might be indicative of the hiker, then we would have an area to go to. But we just have not found that yet.”

Fenn has also chartered a helicopter for three days to look for Bilyeu, calling his disappearance “sad,” according to KOAT.

Bilyeu’s disappearance has also inspired his fellow treasure hunters to look for him as well.

“We know that Randy studied this area very well,” Sacha Johnston, a treasure hunter involved in the rescue effort, told the AP. “He even noted that certain areas were dangerous when the weather was bad, and he had done quite a bit of research. He wasn’t just randomly kayaking down the Rio Grande one day. He knew where he was going. He had a plan.”

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