As promised, a photo of "The Bubble" N.E.G.M.CO. CD 145 in light aqua after it was cleaned in Oxalic acid, much better than the [id=27531045; other photo]. This would be the biggest bubble I have found in an insulator so far. By the way, this is a photo of the insulator from the front, whilst the bubble is in the side, it's really a fair amount larger than this picture shows.