Uncharted 3 Collectors Edition what is the Travelers Chest made of?

When I pre-ordered Uncharted 3 Drakes Deception in Gamestop I saw a poster that said it comes with a Travellers Chest, and that all the bonus stuff comes inside it. I asked the manager at Gamestop if the Chest was Wood,Tin or Cardboard and he could not answer the question. I am hoping Its anything other than cardboard and that its actually something useable.