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Don't breath any of the lume dust in, at that age it's almost certainly radium. :(

'Radium Luminous Paint

The half-life of radium is about 1,600 years, so over the 100 or so years since a watch dial was painted with luminous paint, the radium activity will have decayed about 4%, about 1% for every 25 years. This means that paint that was made with radium 100 years ago will still be 96% as radioactive today as the day it was made. Radium and its fission decay products (such as radon gas) have the potential to cause various health risks, and therefore watches with radium paint should be handled carefully and in ways to minimize these risks. The danger is not so much from radiation received from the watch when wearing or being near to it, but more from inhalation or ingestion of paint particles or contaminated dust'.
 

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John is correct. Wear a mask when uncased. Ingested Ra is recognized as Ca by your body. Even though exposure is likely to be low, no point in inviting issues from even a small amount deposited in bone.

As for age/movement. What are the markings on the mainplate, under the balance?
 

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Don't breath any of the lume dust in, at that age it's almost certainly radium. :(

'Radium Luminous Paint

The half-life of radium is about 1,600 years, so over the 100 or so years since a watch dial was painted with luminous paint, the radium activity will have decayed about 4%, about 1% for every 25 years. This means that paint that was made with radium 100 years ago will still be 96% as radioactive today as the day it was made. Radium and its fission decay products (such as radon gas) have the potential to cause various health risks, and therefore watches with radium paint should be handled carefully and in ways to minimize these risks. The danger is not so much from radiation received from the watch when wearing or being near to it, but more from inhalation or ingestion of paint particles or contaminated dust'.
I didn't know this, so I am glad to have been informed. Thanks for posting.
 

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Discussion Starter #5
John is correct. Wear a mask when uncased. Ingested Ra is recognized as Ca by your body. Even though exposure is likely to be low, no point in inviting issues from even a small amount deposited in bone.

As for age/movement. What are the markings on the mainplate, under the balance?
Actually, won't be opening it again.. :)
 

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it's gold filled not plated. The fact it says warranteed 10 years mean it's certainly pre 1930. They stopped using that term in the 1920s I don't recall the exact date and am too lazy to check the book.

I suspect the case is U.S made.
 

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Discussion Starter #7
it's gold filled not plated. The fact it says warranteed 10 years mean it's certainly pre 1930. They stopped using that term in the 1920s I don't recall the exact date and am too lazy to check the book.

I suspect the case is U.S made.
Found out from Mikrolisk that the MB stands for Th Maeder of Switzerland as the case maker..
 

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Just did a search on 'Haliday' which scratched/engraved above the gold filled engraving..

Found this..

http://www.925-1000.com/forum/viewtopic.php?f=74&t=34374&p=88670&hilit=haliday#p88670

So perhaps case was made by Haliday..
About 150 years too early, wrist watches, as we know them, didn't appear till about the 1880's and your watch dates to the 1920's/30's. Most likely scenario is that 'Halliday' was a watch repairer who did some work on the watch sometime in the last 80 years or so.
 
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