Ghengis Khan, Emissaries medallion?

ok I definitely remember reading a story in National Geographic about Ghengis and his crew tearing about Asia kicking ass and taking names all over the place. also in this article was a picture of a medallion that his emissaries/diplomats carried that gave them protection as well as proof that they were who they said they were.

I am trying to find both a picture of the thing and a translation or printed (as in readable even if its in the original language) version or both.

sorry if this is in the wrong place mods, couldnt think of where to put it.

http://www.metmuseum.org/toah/hd/yuan/ho_1993.256.htm

just in case you are wondering, you sir, ROCK.
never thought to try passport.