Archived posting to the Leica Users Group, 2001/07/27
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]> Hugh Thompson writes: > >> Talking to a dealer this evening and he told me >> that glass in some 1950's M lenses is radioactive, >> and the lenses have added value because of their >> rarity. I thought the radioactive lens was the Thambar. Radioactive to the point that it would fog a piece of paper if left standing on it for a fortnight. Ruby colour cut glass for Eastern Europe is uranium doped for the colour and a lot more radioactive than the Thorium glass mentioned here. Didn't the thorium doped element go cloudy after many years? Oddly enough my local area in England is famous for its Thorium poisoner who work at a photo processing lab and put thorium in his co-workers tea. Regards David Prakel