I found out a lot about the mug. The was made in the 1840's. They were manufactured, but not as we know today. There are 200 of them. They are not known because they are in homes of mostly Jewish families like my mother in law. It's only valued at $350. One has not been sold recently, so not sure what I could really get. The museum was very helpful. Just as interesting I was contacted by an archeologist that I had written to and sent photos. She asked me if she could use my photos and history in a paper. Then she wants to use it for education purposes. I was so pleased to do that.