Updated

The founder of a Chicago hot dog empire thinks he may have a gold tooth that belonged to a Japanese World War II admiral who orchestrated the Pearl Harbor attack and will "do whatever it takes to find out."

Dick Portillo, founder of the Portillo's fast food chain, was on 2015 trip to Papua New Guinea where U.S. pilots shot down Japanese naval commander Isoroku Yamamoto's plane when the tooth surfaced in the mud. A clan that owns the site confiscated the tooth, but later turned it over for $14,000.

"If it comes to be true, it's peanuts compared to the value that I would look at," Portillo told the Chicago Tribune. "If it doesn't, you win some and you lose some."

Portillo said he is working to authenticate the tooth, including contacting dentists and a research librarian. He said it also may be possible to have DNA extracted from a tiny human tooth bit in the gold.

Japanese naval historian Yukoh Watanabe has his doubts. Watanabe, who wrote a 2015 book on Yamamoto, said it's unclear whether the commander's dental records exist. He also noted that multiple people were on the plane.

"I have to say that it is little possibility it belonged to Adm. Yamamoto," Watanabe wrote in an email to the newspaper. But as a fellow romantic of history, he added: "I also hope the gold tooth belongs to Adm. Yamamoto."

Portillo said he wasn't looking to make money, adding that he would like give the tooth to the Japanese government and make a documentary.

"The value to me is the fun, the experience of doing that, the fact that I had a lot to do with it, and history," he said.