Hehe ... you're a bit late to the show Tishers.
Some of us are bit hard core on collecting everything radioactive.
So the history of glow in the dark paint is that Radium was used up until about the 1950's.
Promethium was used in the 1960's and 70's and Tritium has been used since about the 1980's.
Yes, smoke detectors are Am241, though a lot these days are not, they use optical sensors.
Valves - actually no. None of the valves in old radios or TV's are "Thoriated". Thorium 232 is the isotope used in valves that have it.
The high voltage thermonic power diodes weren't Thoriated. The most common kind of tube that does have thorium are RF transmitter valves like a 4CX1000.
Thorium is also found most commonly in old gas lantern mantels. It's also in Thoriated welding rods and some of the high refraction index camera lenses and some gemstones like Ekanite.
Uranium is easy to find in antique shops. The green Uranium glass is very common and glows nicely under UV light. Brewdog and I tend to agree that the better a source glows under UV light the more radioactive it is.
It's a good general rule but there are some exceptions. Uranium glass is typically green, but some is yellow, blue and even pink.
There are also plenty of Uranium glazes. They're typically bright orange, a translucent yellow (which also fluoresces), brown and occasionally green.
Sealed your Radium. Oh that's a shame. Yes the secondary beta/gamma is nice, but Radium is an alpha emitter and so are the majority of it's daughters. Though the 7.7MeV alpha from Po214 has enough energy to penetrate the copper foil.
Pretty much all of the beta emissions will be absorbed by the copper foil. Which leaves only the gamma, most of which will penetrate the copper foil but the amount of gamma radiation is rather pitiful.
Your fears of Radium contamination from a poor old clock face are .... umm... a little excessive. The radium is pretty safely locked up in the zinc suphide crystal and glue.
So take it out of it's copper prison and let the alpha particles be free. It's really not going to hurt you unless you feel the need to lick it, and even then the radium is pretty safe from you
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