Thanks, flying free. I had to go and get a metric converter to figure out how small 2 mm was. Looks like that is about an 8th of an inch. These scuffs are smaller than that, but I would also have to add that Gunnel Nyman is a rare creature in the States, so for me it is not as if I have many to choose from, particularly those that are acid signed. I know for some collectors of musical instruments, for whom originality is very important, a very small flaw can drop the value quite a bit, no matter how the instrument sounds. These are standards placed on them by collectors and dealers, of course, but they are the people that set the price. I still great get pleasure in having a piece of glass that I can look at and touch, rather than examining in a photograph, as a way to understand the designer's and glass blower's intent. So I have some glass that has chips in it (usually purchased pretty cheaply) because I wanted to hold it in my hand. I like the glass for the physicality of it as well as the look of it. That's why Nyman is so nice
And the water interior staining on glass can be removed mechanically using bits of copper wire, water and polishing compound, but it requires a system for sealing it up and tumbling it for a couple of days (this is how bottle collectors clean the inside of their bottles). I've even thought of building one of these contraptions, since they are quite common in the bottle world, but I never had enough stained glass to make it worth the trouble. Interesting idea though.