Beau Ouimette – best known by his YouTube name Aquachigger – had been using a metal detector on the banks of a lake when it picked up something.
As the footage shows, he immediately starts digging into the mud to discover what had caused the detector to go off.
After just a few seconds, he finds what appears to be an ancient blade hundreds of years old.
“Dude,” he exclaims to his cameraman as he runs towards him with his new discovery.
Beau then shows it to the camera and it appears to be in incredible condition.
“While metal detecting for treasure, I was digging a good signal and heard a weird scrape,” he later explained.
“I looked down in the deep mud and saw one of the coolest Native American Indian blades that I have ever found.
INCREDIBLE: An explorer made an amazing discovery after his metal detector picked up something
“It was an amazing metal detecting adventure with quite the surprise!”
The video – taken in the US – has been seen more than 13,000 times since it was posted yesterday.
“That is an awesome find,” one user wrote.
Another suggested: “Looks like a spear point.”
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And a third agreed, commenting: “Incredible arrowhead!”
It isn’t the first time Beau has left his viewers amazed at his discoveries, though.
Last year, he filmed himself climbing down a 20ft well, only to find dozens of snakes lurking at the bottom.
And he also stumbled across a bloody mess of skulls and “satanic” writing when he climbed into an ancient cave.