Actor Nicolas Cage spent $2,000 on a mammoth-ivory knife with a 4-inch blade Wednesday at an Anchorage knife shop -- and joked that he plans to use it at the dinner table, according to gossip site TMZ.com.

We're told Cage fell in love with a Don Dezarn original -- which featured mammoth ivory in the handle and a patriotic bald eagle engraved onto the 4-inch blade.

The knife is primarily used as a decorative piece, and one knife expert tells us it's common for people to wear similar blades as a holstered accessory with a "nice suit."

TMZ posted a picture showing Cage at the store counter. He's in Anchorage for the filming of "The Frozen Ground," based on the story of serial killler Robert Hansen.