I need to know what colour radium glows in the dark. I have consulted many sources (the internet, my chemistry textbooks…). All of them say that radium fluoresces. None of them say what colour it fluoresces at. Wikipedia says it’s blue but all the pictures I’ve found of luminous clock dials and the like are green. I seem to recall a biography of Marie Curie I read a few years back describing it as pale blue but I can’t find the book anymore. Argh, what colour is it?
There’s a joke here about Curie dying of radiation poisoning, but I won’t make it.
I’ll just post because I’m also curious and want to know.
I don’t know the specific answer to your question, but the green glow you see on modern watch and clock hands and dials is not radium. Radium has not been used for this purpose since the late 60s. Modern watches and clocks use a either a non-toxic phosphorescent paint, or a tritium-containing fluorescent paint. Tritium is still radioactive, but as a weak beta-emitter, it’s considerably safer than radium.
Pure radium has a faint blue glow. When mixed with zinc sulphide they glow with a brighter green color; that is what was used as luminescent paint.
http://www.orau.org/ptp/collection/radioluminescent/radioluminescentinfo.htm
I was talking about the pictures of wartime clocks I found on Google, actually, but I’m not sure if it’s just the paint that was green or if they actually glowed green too, since I don’t think any of them actually glow anymore. Hum.
Argh. And the prize for most instances of “actually” in a sentence goes to…
Wait, did I say “fluoresce”? I meant “luminesce”. :smack: Way to look intelligent, C#M.
I just moved into a high rise apr and discovered my shower drain glows blue; there is no natural light. I am wondering if this is due to the previous tenant undergoing some form of radiation therapy such as thyroid treatment. If this radioactivity is due to this or something like it, what is needed to protect the next tenant?
Even if the previous tenant peed non-stop in the shower after receiving thyroid radiation treatment (with pee being the only significant source of radiation post “thyroid radiotherapy”), the radiation would come from I[sup]131[/sup] which doesn’t glow, in any color.
ETA: After several days, the residual radiation after thyroid I[sup]131[/sup] treatment is negligible in any case.
Does it glow blue all the time, or only during the day?
Ringworm? Eeeewwwww!!!
Sorta tangential, but as a child, I wanted to be a geologist. When I was 12 years old, my parents gave me a “rock collection” kit for Christmas. Included in it was a chunk of uranium ore (carnotite)-which also contains small amounts of radium. I had the rocks on a shelf in my bedroom, and I noticed that after the lights were turned out (and my eyes adjusted to the darkness), the carnotite piece would exhibit a faint blue glow…was I being poisoned?
Yes. You will probably die within the next 7 decades.
Damnable zombie threads. And here I was all excited because I knew that radium-painted watches were only bright green because of the zinc sulphide.
Only 7 years too late to be of service.
Fun trivia fact: the girls who painted the watches with radium were told to use their lips to shape the bristles of the brushes, as their saliva would help make the tips stiffer, and therefore more precise in painting the dials and markings. After a while at work, their hair and nails would glow faint blue-green in the dark, making them very popular at parties. :eek:
Not so fun fact: many of these girls died of radiation poisoning, or were disfigured when their jaw bones rotted away. A group of them sued the company and won, establishing the right for workers in the US to sue their employers for damages from occupational illness.
Nitpick: I-131 has half-life of ~8 days. I used to dole out ‘treatment/ablation doses’ being a Nuclear Med Tech, and it was standard to tell patients that they needed be attentive to their wastes (and proximity-time of others to their ‘hot’ thyroid gland, like holding babies or spouse snuggling close while asleep, etc) for about a month or so max (less with smallish doses). Maximum dosing for outpatients was (is?) below 30 mCi - higher required hospitalization and special handling of body fluids/wastes until levels dropped (per NRC regs). We did not do in-patient dosing levels. This was during the '90’s, too, so things may be different now.
From here: Radiation detection devices used at airports and federal buildings may be sensitive to the radiation levels present in patients up to three months following treatment with I-131. Depending on the amount of radioactivity administered during your treatment, your endocrinologist or radiation safety officer may recommend continued precautions for up to several weeks after treatment.
ETA: no glowing or such could occur from I-131, though MANY patients asked if the stuff caused anything as such. I fought their ignorance best I could 
Maybe your region just has really hard water, and it contains amounts of light-emitting minerals/elements?
Is this even possible? 
“Need answer fast”?
If so, you got problems…
Is it not the yellow/green color of watch dials and old aircraft instruments?
No, that’s the Zinc Sulphide glowing, excited by the Radium.
According to Wikipedia, Radium glows a faint blue.