Thanks folks - agreed. An old cleaning/dipping hadn't occurred to me but I guess that's a possibility. Not a problematic one I would say. This sucker is quite rare...PCGS has only ever graded 4 of them: 30, 35, 40 and 50. This one is the 30 and I would say that's fairly accurate....perhaps a tad generous. I would have said 25 but it's possible that's splitting hairs.