Follow CBSMIAMI.COM: Facebook | Twitter

KEY WEST (CBSMiami) - A major development this morning in the mystery of the gold bar stolen from a Key West museum.

CBS4's Jim DeFede reported on the heist earlier this week.

On Wednesday Jarred Goldman, the so-called lookout for the theft at the Mel Fisher Museum, was convicted by a federal jury in Key West.

Goldman said he didn't know his friend, Richard Steven Johnson, was going to steal the 400-year-old gold bar from its case in the museum in 2010.

The crime, which garnered international attention, had remained unsolved for almost eight years until a tip led the FBI to Johnson, who pled guilty earlier this year. Both men are now facing 15 years in prison.

One mystery remains - what they did with the nearly five-pound gold bar. Only a tiny sliver has been recovered.