My first impression was the stamp is a date code. Which makes it either 1872, which would make it a antique, or 1972, the later I was leaning towards. I did look around in my books and surfed a bit, and did find a small blurb on a J. Foss but the date was early 1900's, and not much, or enough to make a discission on the date. Just a first glance it does not look old enough for 1872. Without hallmarks, and just a signature to go on the wall is thick and tall. It does appear to be what is called Flow blue, but that would help little in your search. My conclusion is you have a vintage at best piece that value would be low. The others may have a better knowlege and books to help reference it.