Antique Teapot (pics)

Before my mom passed away she gave to me a teapot that belonged to her mother. I love having that teapot and have always been curious about it. I thought it was pewter at first because of its color, then thought because it doesn't say sterling it may have been silver plate that just got worn off over the years. I've had it a long time now and took it out the other day to examine it. It looks very old and looks almost handmade with lots of hammer-like marks on it. I took some Tarn-x to the lid and it turned silver, the brite white color of coin silver. Yesterday I put Tarn-x on the rest of it and it sure doesn't look silver-plated as there is no corrosion anywhere. It is very heavy for its size. I want to find out if that is a family coat of arms or a company logo on the side, my grandma's family crest maybe? I'm going to do some research at the bookstores and library and see if I can figure it out on my own. Then I'll try one of those online appraisals and see what they say and to see if they are worth using. I know silver teapots are not worth much, I just would like to know the history. I'll blog the results when I get them. Here is my teapot before and after polishing.