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A question for those knowledgeable about radioactivity

Nordhavn

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WWII radium disks were pretty bright. They used paint containing radium salt and zinc sulfide as a scintillator. They were also quite dangerous and to this day, if you had one, they would be quite "hot" indeed! The markings on old aircraft altimeters are still sought after these years for test sources. The ZnS "targets" are utterly trashed by the radiation so they don't glow but they are good sources for alpha and gamma if you need them.

I remember in my youth having a radium dial watch and alarm clock and in the wee hours of the morning, long before the sun came up, waking to see a very interesting flickering of the dials. Looking at them with a magnifying glass was fascinating as you could see the bursts of scintillations, almost like looking at a polymicrobic sample on a slide under a microscope!

Here's what it looks like:

https://www.youtube.com/watch?v=rac-zsm-B_k#ws

An instrument called a spintharisccope is based on this principle. A disk painted with radium paint is on one end of a cardboard tube and an aspheric lens of medium strength on the other. Peeking through the lens with dark adopted eyes revealed an amazing sight indeed! When alpha particles struck the ZnS scintillating agent, a burst of light is emitted and visible. Was like watching lightning in a bottle.

In the 1950s Gilbert Corp, a mfr of chemistry learning sets, put such a device in their nuclear based set. I had one and it was amazing. Not exactly safe for a boy to play with either. ;)

They even put these in cereal boxes, known as the Lone Ranger Atomic Bomb Ring! Well not quite, you had to send in box tops. This was before UPCs which came out in the 70s. Hehe

https://www.orau.org/ptp/collection/spinthariscopes/ring.htm
 
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Blarg King

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So basically the only safe and legal way to go about it is to either buy a beta-voltaic device or build one from tritium tubes.

The only thing else I could find would be to take Americium from a smoke detector, put it in a vacuum and aim its Alpha radiation at a piece of metal to create a charge difference, but I'm doubtful that the tiny Americium source would be able to create any significant difference in charge.
 

Nordhavn

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One microcurie of Am241 is quite infinitesimal indeed. There are larger ionization chambers used on commercial hvac duct detectors that may have fifty times this quantity but it's still too small to amount to much.

A few bags of thorium doped lantern mantles would be more effective. ;)
 

Blarg King

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I've tried finding thorium lantern mantles but they've either been banned in Canada, phased out, or my geiger counter can't detect them.
 

Blarg King

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Though theres still thoriated tungsten electrodes being sold at welding shops. Its only 2% though so I doubt its useful.
 
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Nordhavn

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A two pound chunk of uraninite works! I have such a specimen acquired from Africa. It clocks about 85mrem/hr (gamma!) according to my counter. In a dark room one can see sparkles like lightning. These sessions are best kept short for obvious reasons!
 
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paul1598419

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That's funny as I had a radium painted alarm clock when I was a kid too. They would glow in the dark no matter how long they sat. I guess everyone thought they were harmless back in the 50s. Marie Curie was likely killed from radium exposure, though she was 68 years old at the time. I think she died from aplastic anemia.
 
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Blarg King

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Sad thing is getting good chunks of rock with uranium in it off the interwebz is getting harder and harder. Only a handful of listings on ebay and they're quite pricey.

Supposedly though the province I live in (NewBrunswick) is just chock full of natural uranium (thats why a province with less than a million people gets a nuclear reactor. And radon leaking through our floors) I should just go out into the woods with my geiger counter and see if I can find some on my own.

I've never heard of radioactive ore causing sparkles though. What causes that?
 

Nordhavn

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Most likely caused by the radium in the ore. The alpha activity is super crazy. The thing would probably look like a lumibrite coated tennis ball tossed into a rave if I coated it with ZnS paint!
I also have a bottle of paint for touching up radium dials. It's part of a kit that was produced in the 1930s. It only glows briefly if exposed to 405nm. However, those flashes can be seen (lightning in a bottle effect!) continuously and the vial itself is quite hot. Alpha doesn't get through the glass but the gamma, around 35mrem/hr sure does!

Ores aren't regulated by the local and federal nuclear regulating agencies as they're natural sources. But send something like that rock through the mail and I'm sure trouble will ensue quickly!
 

Seoul_lasers

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Sad thing is getting good chunks of rock with uranium in it off the interwebz is getting harder and harder. Only a handful of listings on ebay and they're quite pricey.

Supposedly though the province I live in (NewBrunswick) is just chock full of natural uranium (thats why a province with less than a million people gets a nuclear reactor. And radon leaking through our floors) I should just go out into the woods with my geiger counter and see if I can find some on my own.

I've never heard of radioactive ore causing sparkles though. What causes that?
The device in question that allows you to see sparkles with your eye is a Spinthariscope. Some of the hotter Uranium ore samples can liberate enough alpha particles to cause the ZnS screen to scintillate.
Uranium ore is still very easy to obtain in the mail, and I know of a few venors here in Canada that ship.
jimtherebel, fission236 and a few other Ebay members ship to Canada or are in Canada.

Radium, I must point out occurs in very miniscule amounts in nature, even in decently active uraninite samples... not enough to be reliably visible on the spinthariscope per se. However, when Uraninite occurs alongside barite there is a tendency for a very tiny amount of Radium 226 (3-5Bq worth) to replace Barium as the two elements are found above each other in the periodic table. Both are members of the Alkaline earth metals Group 2A .
A mineral called RadianBarite (Ba,Ra)SO4 forms when the conditions are right for a replacement to occur, again... only few atoms of radium are in any given sample at any one time...


shipping ore samples...
I must also point out while ore samples aren't regulated either in Canada, surface Radiation monitoring is being done more often,
and if your package has a high surface activity it could be pulled.
 
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Seoul_lasers

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I've tried finding thorium lantern mantles but they've either been banned in Canada, phased out, or my geiger counter can't detect them.
Some still around... found some at Canadian tire.. :eg:
You're right of course, most of the Thorium mantles have been replaced with cerium oxide.
 

paul1598419

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Uraninite is what we used to call pitchblende. That was the ore Marie Curie refined most of her life to get radium from.
 

Blarg King

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Theres still a few people selling them on ebay, but their prices are quite high for the most part. Most the listings I see start at 300$ an go up to 600$. I paid 30$ plus shipping for my 2 inch long ore sample a few years ago.
 

paul1598419

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Pitchblende was dirt cheap when I was a kid. Had some in my rock and mineral collection. There's no good reason for it to be so expensive now. I think it is people taking advantage of buyers on eBay.
 

Nordhavn

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Uraninite is what we used to call pitchblende. That was the ore Marie Curie refined most of her life to get radium from.

Yes that is correct.

And the sample I mentioned previously is actually uranophane. It's mostly a yellow color and quite flaky and thus rather dangerous to handle for untrained folks.
 

Encap

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Interesting web site with natural radioactive material for sale, see: RadioactiveThings.com

Photos of the largest piece of pitchblend ever found, a 7/8 of a ton chunk ~ Australian Museum and a super grade uranium ore sample, 133 pounds, 80% uranium ~ American Museum of Natural History. see: The Largest Piece of Pitchblende Ever Found | RadioactiveThings.com

Samples of many radioactive minerals are available/for sale, here: URANINITE & OTHER RADIOACTIVE MINERALS

Yes that is correct.

And the sample I mentioned previously is actually uranophane. It's mostly a yellow color and quite flaky and thus rather dangerous to handle for untrained folks.
Uranophane--beautiful crystals!! See; https://www.dakotamatrix.com/mineralpedia/8005/uranophane

 
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