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Thread: Cyma WWW lume, Radium or Tritium?

  1. #1
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    Default Cyma WWW lume, Radium or Tritium?

    I try to figure out the lume material on cyma WWWs
    is it correct that all of them made with Radium lume but later relume with Tritium by MOD?
    thats why I always see theres like two type of lumes?
    most obvious the hands lume, they comes with normal size and a fatter lume
    (or I was wrong? there's no such thing?)

    like these two from my watch buds

    are these two with two diff lume material or not?

    thanks in advance




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    Thats a good question, I'll be waiting for an answer too as I think this watch is going to be next on my list.

    I also noticed the flat and fatter hands. But i always assumed all the greenish/whitish lume to be MOD tritium, and original radium to be the dark brown/orange ones?

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    Moderator dave's Avatar
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    the original 1945 factory dial and hands would have been lumed with radium.

    later on the radium lume on the dial and hands was replaced with tritium lume.

    here's my opinion on the two watches posted -

    both watches are fine.

    in both cases it would appear that the lume has been upgraded to tritium lume.

    the hands on both watches are the same - the bottom one has what I call a fat finger relume.

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    so fat or flat lumes dosent indicate the lume material on Cymas
    then how to differentiate them ?
    patina color? Radium is dark orange/red ?

    thanks guys anyway

    Quote Originally Posted by dave View Post
    the original 1945 factory dial and hands would have been lumed with radium.

    later on the radium lume on the dial and hands was replaced with tritium lume.

    here's my opinion on the two watches posted -

    both watches are fine.

    in both cases it would appear that the lume has been upgraded to tritium lume.

    the hands on both watches are the same - the bottom one has what I call a fat finger relume.

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    Quote Originally Posted by bloodkrishna View Post
    so fat or flat lumes dosent indicate the lume material on Cymas
    then how to differentiate them ?
    patina color? Radium is dark orange/red ?

    thanks guys anyway
    You'll have to get a radiation (Geiger) meter (Radex, etc) and measure the radiation coming off the watch.

    Tritium has a half-life of around 12.5 years so should be much but not entirely depleted by now if it was applied to the dial and hands 60+ years ago. Also the beta radiation emitted by tritium decay can't pass the crystal so the radiation meter should barely be able to detect any radiation if it is tritium.

    Radium on the other hand has a half-life of 1,600 years and should still be quite hot and most worrisome is that the gamma radiation emitted by radium decay can easily pass through the crystal and into skin.

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    Quote Originally Posted by Reintitan View Post
    Radium on the other hand has a half-life of 1,600 years and should still be quite hot and most worrisome is that the gamma radiation emitted by radium decay can easily pass through the crystal and into skin.
    I wonder about wearing a watch with original radium lume regularly. Obviously the MoD was concerned enough to relume all watches still in regular use.

    If a watch is staying in a case or on display it's one thing, but if you are using it on a routine basis Is the radioactive properties of radium something to actually be concerned about?

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    about health problem
    I suppose we shouldnt be so worry as I guess all of members here
    dont wear a same piece all the time?
    I personally swap pieces everyday

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    Senior Member papazulu's Avatar
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    Quote Originally Posted by bloodkrishna View Post
    about health problem
    I suppose we shouldnt be so worry as I guess all of members here
    dont wear a same piece all the time?
    I personally swap pieces everyday
    You'd be surprised what radiation dose comes out of a Mil-Watch, about the hottest I've seen and measured came out of a Hamilton 987A...look at the radiation burns on the dial, I'd rather not show you what I measured with a Gamma-Scout
    Don't talk to me about naval tradition. It's nothing but rum, sodomy and the lash.
    Sir Winston Churchill

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    Quote Originally Posted by papazulu View Post
    You'd be surprised what radiation dose comes out of a Mil-Watch, about the hottest I've seen and measured came out of a Hamilton 987A...look at the radiation burns on the dial, I'd rather not show you what I measured with a Gamma-Scout
    woah you are in big risk
    please send the watch to me

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    Member isologue's Avatar
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    Quote Originally Posted by Dtle View Post
    I wonder about wearing a watch with original radium lume regularly. Obviously the MoD was concerned enough to relume all watches still in regular use.

    If a watch is staying in a case or on display it's one thing, but if you are using it on a routine basis Is the radioactive properties of radium something to actually be concerned about?
    Remember that MoD and other authorities were worried about the *cumulative* effect of radium when many sources were stored in the same place - not necessarily just watches, but other instruments too. This is not to underestimate the harmful effects of radium at all (and, with that in mind, you might want to consider storing your *collection* of radium emitters in a lead lined box rather than a glass cabinet.....) Inhaling radium or ingesting it is of course very dangerous, but personally I don't worry about the occasional radium source strapped to my wrist so long as the crystal provides a seal and the radium is intact. Not that I am an expert.

    Regards,

    Martin (isologue)

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    Member Syrte's Avatar
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    There have been several discussions about the possible health effects of radium, one of them you will find by searching the words "radioactive" and "bulova"... lots of info (and good jokes) in there, including links to highly technical discussions.
    Best regards,
    S

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    Senior Member papazulu's Avatar
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    Quote Originally Posted by bloodkrishna View Post
    woah you are in big risk
    please send the watch to me
    You may not joke after you have seen this?
    Don't talk to me about naval tradition. It's nothing but rum, sodomy and the lash.
    Sir Winston Churchill

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