In Star Wars: Episode I – The Phantom Menace, what is Qui-Gon Jinn's communicator prop made out of?

It may sound like something out of The Simpsons, but after my friend waited all night to secure tickets to The Phantom Menace, I had the death of Jedi Master Qui-Gon Jinn spoiled for me by the dude in the comic book store.

Still, my excitement for the first new Star Wars movie that I was actually reasonably conscious for could not be tamed. I don't care what people say now, everyone was excited as hell. It was a huge moment in movie history. Hell, I think I saw it at least six times in the theater.

With all those viewings, you'd think I would have picked up on this interesting detail. For all the CGI and high-budget sets built for the movie, which had a budget of $115 million, there was one prop that was built from an otherwise mundane item.

For the eagle-eyed, you might have noticed that the communicator Qui-Gon uses is built on... what?