Very Old Mystery Teapot

While I consider myself knowledgeable in lots of old things, this teapot has me stumped! It looks quite old, but I'm not sure exactly how old... At least 100 years, I'm guessing. There are markings on the bottom, but one of them has worn nearly completely off. It had what appears to be some kind of leafy crest stamped on the bottom. There are two other markings which are clear, however, but still I don't know what they mean. Any help would be greatly appreciated!