www.925-1000.com

This one is pretty banged up, but seems of interest for the marks and design. After the stamped "800" is a rectangular box that seems to have been (a partial of) the makers mark...no crescent and crown visible, but possibly figural elements. It's largely unreadable for any positive identification, but few German makers seem to have used a like device. One Hanau firm might point in that direction....perhaps the decorative elements might shed more light on a likely origin? At any rate, it's a sample of someone's work:

Hello, Hanau is certainly a possibility, but we need sharper images of the mark from all angles, I am afraid. Regards, Bahner

Thought I detected a letter while viewing the mark upside down. Yes! Cleaned mark...Finally found oblique angle and clearly spotted letters "W" and "Z" flanking sides of central object. [If you saw the things I tried to construct to photograph this, you would die laughing.] The image will never match up to what the naked eye can see, but hopefully it will transmit here without too much degredation. I am certain of the "W" and that it is not a crown. We can only see part of the "Z", but it should be enough and a "2" seems not likely. That leaves the center blurr...maybe an animal profile like bird facing right, or God knows what? I could not find such a "WZ" maker on this site...only an Austrian Vienna A/WZ which cannot relate. Perhaps it has surfaced in another place?