Uranium Glass - F-J's Physics - Video 190

[@AnthonyFrancisJones]

Please consider supporting my work by buying me a coffee at www.buymeacoffee.com/francisjonesa Helps me buy bits and pieces to make these videos! Very many thanks, F-J

[@StandardTacticalKnight]

Fantastic demo! Thanks for showing this!

[@AnthonyFrancisJones]

My pleasure! Glad you found it interesting.

[@TN-id4yx]

Interesting! Thanks for the video

[@AnthonyFrancisJones]

Thanks. It's interesting stuff isn't it!

[@tuopeeks]

Uranium glass must be a good school demonstration given the activity is low but detectable compared to other sources. It can also be found used in large old vacuum tubes/valves due to its better metal to glass sealing properties. Worth looking at old transmitting tubes under UV, particularly where the metal to glass seals are. Another nice test/demonstration source is old gas mantles. They have quite surprising activity from the thorium used in them, but maybe less suitable for demonstrations.

[@AnthonyFrancisJones]

Yes, I think this is a good demonstration of fluorescence but not really radioactivity as the count-rate is so close to background with a GM tube. I don't think I have any of the vacuum tubes with this glass in it - used for large vacuum capacitors too. Most of my examples seem to use a special sintered glass like the CV2799. Schools (under licence) can still have sealed radioactive sources of an approved type but gas mantles are usually frowned upon due to the dusty nature of the Thorium Oxide. So much has changed in the years I have been teaching but I do hope children still see things demonstrated in a safe way. I have an old TEL-X-Ometer but need to fit a tube to it!

[@tuopeeks]

@@AnthonyFrancisJones yes indeed, dust from mantles would concern me too. Although that must have been common when they were extensively used. I remember seeing the TEL-X-Ometer as a student. The tubes appear now and again but seem pricey. It also took me back to a school lunch time experiment where my physics teacher and I tried to fog photographic film using just an old TV diode valve. Unfortunately, not an experiment that would be repeated in schools today.

[@AnthonyFrancisJones]

Interesting! Yes, one has to be careful about that type of 'exciting' experimentation these days! Sounds like you had inspiring teaching regardless of the possible risks!

[@GeoffryGifari]

Hmm so the green tint (under sunlight) of the glass is a separate phenomenon to the UV fluorescence? maybe thats why "radiation" is often associated with green glow in pop culture

[@GeoffryGifari]

And also, UV fluorescence comes from _molecular_ bond right? so its related to Coulomb attraction of uranium nuclei but not really a nuclear phenomenon like decay

[@AnthonyFrancisJones]

Geoffry, not quite, you are right it is not a nuclear phenomenon as it does not directly involve the nucleus. Nor is it due to bonding directly either. It is the electron configuration in atoms that is the cause. Simply, some atoms electrons can be promoted to a higher energy level when they absorb UV light and then the electron falls back via a number of lower value energy jumps emitting a photon of lower wavelength (green) light each time. I think in this case it is due to the ionic configuration of the uranium atom but I am not totally sure which electrons are responsible.

[@NoahSpurrier]

Uranium was also used in ceramics for bright orange glazes. See Fiestaware, Fiesta Red.

[@AnthonyFrancisJones]

Thanks Noah, yes that's right. These glazed items were not so common in the UK but were around a lot in the USA. Their more modern glazes look the same but do not contain the same additives. I don't have an example of original 'uranium' Fiesta Ware sadly but I love all the colours they did!

[@GeoffryGifari]

Would radiation compromise the structural integrity of thos wares over time?

[@AnthonyFrancisJones]

Geoffry, that is an interesting question. Vitrification (putting in glass) is used for high level nuclear waste and there are issues with embrittlement etc. I think the item would have long been lost/broken by then!

[@shivenprashar1427]

So does it contain uranium ?

[@AnthonyFrancisJones]

Yes it does, probably billions of atoms but that is still a very small amount! The main thing is that the half life of the uranium in the glass is so long!

[@shivenprashar1427]

@@AnthonyFrancisJones do can we like melt the glass And then as uranium bight be denser so it will just you know do downwards I don't know I don't have like so much experience

[@AnthonyFrancisJones]

No it is not in the metallic form in the glass. It is part of a oxide form of uranium and that would need some complex chemistry to extract as well as the end result would be very little U238.

[@shivenprashar1427]

@@AnthonyFrancisJones thank you By the way Any channels you would support for this type of chemistry and stuff or any books you would recommend

[@AnthonyFrancisJones]

That's a tricky question as most of my ideas come from years of teaching and lots of varied sources! You might enjoy the amazing channels that are The Action Lab and Applied Science and perhaps Nile Red too. Books, again, my content is rather too spread out for any particular book. I did enjoy The Radioactive Boy Scout, a true story about a boy trying to build a nuclear reactor in his own house! I do have a collection of old school practical science books and they often have lots of interesting ideas in them. Sorry not to be more helpful but hope you continue to enjoy my varied output!

[@david_pilling]

Interesting, but disappointing, looks like one banana worth of radiation. KZbin gold would be getting a car boot abandoned for the levels of radioactivity found in old stuff. Best story I heard is that the material that glows degrades a lot faster than the radioactivity, so watch dials and the like may be hotter than they appear.

[@AnthonyFrancisJones]

David. The radium in dials has a half life of around 1600 years so the paint binder falls apart and causes it to flake off well before then. The main decay is to Radon too! The glass is about 1BED (is that the correct unit abbreviation?). Perhaps '1 coffee' too! It is interesting that some people are disappointed about the radioactivity of this glass thinking it was made to be radioactive, however, it is just a byproduct of wish for a nice green colour. As you know there were many intentionally radioactive 'heath' items back in the day, to be avoided now! Thanks as ever for watching.