This is an odd question, but can a coin die effectively strike and create a relief design that has a rim angled like a chapter ring on a watch? I know that there are concave coin examples that were made with unique challenges. My example, however, would be much more steep. I'd think that rim area of the die can't simply have a "straight" incuse design, or it may "smear" as it struck and cause something like an MD effect. Or maybe if it's struck hard and fast enough it wouldn't matter (?). Here's a pic of a chapter ring with a dial to illustrate what I mean by an inwardly angled rim. Maybe this is a question for someone like @dcarr (I can't get the hyperlink to appear for some reason). Thanks in advance!