A Florida man was left delighted last week after finding a tooth fossil from a megalodon, the largest shark to ever live.

Michael Nastasio said he was “so happy” when he found a 6-inch-long megalodon tooth while fossil hunting off the coast of Venice.

The megalodon, also known as Otodus megalodon, was a huge shark and apex predator of the seas that is thought to have gone extinct around 3.6 million years ago.

The earliest fossils date from around 20 million years ago, suggesting that for around 13 million years the enormous fish dominated the oceans, according to the U.K.’s Natural History Museum. The museum describes the shark as the largest to ever live.

Researchers have never found a complete megalodon skeleton, but based on the sheer size of the animal’s fossilized teeth, it is estimated that it grew to between 49 and 59 foot in length. The largest megalodon teeth to be found have been in excess of 7 inches.

On his huge 6-inch find, Nastasio said in a Facebook post that he had been hunting for a tooth of that size for around a decade. He is the boat captain at the Florida diving company Black Gold Fossil Charters.

“I’m so happy right now and literally still shaking,” he wrote. “I was the last one in the water and saw it within the first five minutes of my dive. The tooth measures 6 1/16 [inches].”

He also posted photos that show him holding the tooth, which looks to be around the same size as his hand.

Megalodon shark teeth can be valuable depending on their size. Fossil website FossilEra allows people to buy and sell megalodon teeth, and while some examples can go for a few hundred dollars, others, such as a serrated 6.21-inch tooth, are valued at nearly $3,000.

Megalodon teeth have been found on every continent except Antarctica. Many examples have been found off the east coast of North America, as well as in rivers in North and South Carolina and Florida.

Earlier this year a three-pound, 6.45-inch tooth was found at a construction site in South Carolina. Outside of the U.S., a 4.3-inch long tooth was found this year in the U.K. on the Naze—a headland on the coast of Essex.

Megalodon teeth are relatively common fossils because sharks produce so many of them. Depending on what they eat, they can get through up to 40,000 teeth in their lifetime. Their teeth are also the hardest part of their skeleton.

Original Article: Florida Man Finds Tooth of Megalodon, Biggest Shark to Ever Live, While Diving