Two treasure hunters claim they found the Le Griffon shipwreck in Lake Michigan after it disappeared more than 300 years ago. Kevin Dykstra and Frederick Monroe brought back just one artifact from the shipwreck that might prove everything: a nail.

According to FOX17, Kevin Dykstra and Frederick Monroe were originally searching for gold in Lake Michigan in 2011 when they stumbled on what they now believe to be the Le Griffon shipwreck.

The two treasure hunters were taking measurements of the ship when Dykstra's magnet on his scuba gear picked up an object that few people have ever seen: a hand-forged nail that dates back to 1679.

The nail is believed to have been on board the ship at the time of it's disappearance and being transported for building purposes. Historians have since inspected the nail, which is the only artifact to be brought back from the shipwreck so far. Many explorers have claimed to have found Le Griffon in the past, but Dykstra and Monroe are the only ones who've found an actual shipwreck.

Dykstra and Monroe took plenty of photos while underwater, including old cannons, a sword, and the bow of the ship with a carved sculpture resembling a griffon.

"If you take the picture of the carving of the griffon and overlay it on what these gentleman have, it's very compelling," Porter said. "It's the holy grail of shipwrecks in the Great Lakes."

Le Griffon was built by French explorer Robert de La Salle, who was exploring the Great Lakes region in the 17th century. The vessel is said to be originally designed to haul furs from the Green Bay area to Detroit.