BEAUFORT, N.C. - A research dive will begin Wednesday to recover a cannon and other artifacts from a sunken ship some believe belonged to the pirate Blackbeard.

Researchers plan to conduct the expedition over 12 weeks, making it the most extensive effort yet, according to a news release from the North Carolina Department of Cultural Resources.

There are differing opinions as to whether the ship is the Queen Anne's Revenge. But researchers who spent at least US$2 million recovering artifacts off the central North Carolina coast haven't found anything to rule out that the ship belonged to Blackbeard.

Besides the cannon, divers plan to recover two pewter plates and gold dust, officials said.

"We'll also work in the stern and aft hold areas, which are rich with artifacts from the captain's cabin and officers quarters," said Mark Wilde-Ramsing, the project's director.

Historians believe the Queen Anne's Revenge ran aground in Beaufort Inlet in June 1718. State archaeologists have researched the shipwreck for 10 years, but are still waiting to find an indisputable link to Blackbeard.