Japanese tea set

I have a japanese tea pot set, it has 4 cups and a large plate. I think it  is made out of clay, then it has a dragon overlay type of design that is either silver or some kind of metal. Im not sure. I also have the original box. The box isnt in the best shape, but stil holds the set. I took it to an antique dealer once before and he figured it was real silver and the set came from japan during WWII. whether or not it did, I dont know. I would like to know where the set is from, how old it is and an appraisal value if possible.

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