The rim appears to have been fire polished but in places is flat, I don't think it has been ground, it also has a very small mark which could be a fault or a tool mark. There are similar ones to it on Ebay with doubtful attribution to Walsh, the cut part certainly looks like Walsh but I'm not convinced the fruiting vine does. There is a similarly shaped tumbler at the bottom of figure 289 in Eric Reynolds book but I can't see any detail or read the description.