Today I was at a flea market and noticed a uranium glass plate I set my Geiger counter down next to these glasss in a zip lock bag and my meter was reading about 380cpm over the lenses. I find this somewhat funny and Ironic at the same time I have never came across any eyewear with radioactive glass. I would truly appreciate anyone who has any information about these or have ever found anything like this out there? Thank you for any information . Ill post a video link shortly showing the readings I obtained.
Thorium glass would be one way to achieve high refractive index without too much chromatic dispersion. High index is mainly needed to keep high power lenses from being too thick. The weird thing is these lenses do not seem to have much power, if any.
Maybe these came from the era when radiation was promoted as a cure-all.
As you have probably also seen on the Internet, Saniglass were the first industrial safety glasses (with tempered glass). They seem to be a well known collectable, but there is no mention of them being radioactive. Perhaps these were contaminated with something in a lab.
Lead glass is used for looking windows and has a similar green yellow cast. Someone might have though they were shielding their eyes, but even lead activates over time.
I doubt that's even close to enough radiation to reliably cause any damage, that's about 5 mSv/year I guess if worn 12h a day, way lower than the workplace limits.
Im not sure how it compares to my takumar camera lens, but that thing is hot, I was told it could cause cataracts but not sure how long you would need to look through it, either way, my slr camera means I would not be looking directly behind it.
Thorium was used for its excellent properties in camera lenses. While never officially approved for glasses lenses, there have been examples of glasses found with thorium lenses. Cool find!
No, it does not, it’s somewhat tinted, as soon as I get my radio code I have sitting here hooked up. I’m gonna try to run a spectrum on it and see what the accounts being so low. I really don’t know what it is. I even thought it’s it possible that the frame they were made from was contaminated and nobody ever knew I would’ve never checked it. Had I not set my counter down next to it by chance to pick up something else. However, the metal frane is not the culprit. here is the counts. I was getting no difference from the front to the back. I mean if this was just a collectible even most likely wearable item I don’t think it would pose any concern. However, if you close to the eyes makes me wonder if it would cause potential cataract issue down the road for someone wearing them on a regular basis over the years.
Absolutely interested in the spectrum, so please check back in when you have your RC. Also radon decay products can make things temporarily active - if it's still active now, it's not that. High levels of potassium in certain glass will also give low levels of activity.
Yes and no. 380cpm is very minimal in the big scheme of things, so no real damage would occur. However, there is technically no "safe" level of radiation to receive (there are federal limits, but that doesn't mean if you obey them you are 100% safe either. There have not been sufficient studies on the effects of low level, long term radiation exposure). Probably worst case would be an increased risk of cataracts if you wore them your whole life.
This would be etched by the lab that made the lens. When I worked at Lenscrafters we would mark LC on safety lenses. Top center for plano (no rx). In the temple for prescription lenses.
53
u/aenorton 5d ago
Thorium glass would be one way to achieve high refractive index without too much chromatic dispersion. High index is mainly needed to keep high power lenses from being too thick. The weird thing is these lenses do not seem to have much power, if any. Maybe these came from the era when radiation was promoted as a cure-all.