Now EXreaction, that is a time consuming task to "look up" pottery marks being there are literally thousands of them.
If someone recognizes one, they might tell you, but few will spend hours researching it for your benefit only. Now I have 2 hardbound books of "pottery marks" and unless it is one I am really, really interested in, or know exactly where to look, neither of them will be opened up. But now that is just me of course. cheers