[HN Gopher] Europium UltraGlow Powder - Green
       ___________________________________________________________________
        
       Europium UltraGlow Powder - Green
        
       Author : graderjs
       Score  : 141 points
       Date   : 2023-02-06 16:42 UTC (6 hours ago)
        
 (HTM) web link (unitednuclear.com)
 (TXT) w3m dump (unitednuclear.com)
        
       | Majestic121 wrote:
       | Are there specific restrictions on this ? I get
       | 
       | ``` Access denied Error code 1020 You do not have access to
       | unitednuclear.com.
       | 
       | The site owner may have set restrictions that prevent you from
       | accessing the site. ```
       | 
       | Connecting from work and mobile
        
         | realYitzi wrote:
         | Use a VPN
        
         | HansHamster wrote:
         | http://web.archive.org/web/20230206165943/https://unitednucl...
        
       | throwaway743 wrote:
       | Isn't this Bob Lazar's company?
        
       | abotsis wrote:
       | Wait, what:
       | 
       | 8 ounces ( $70.00 ) (1lbs) 16 ounce ( $130.00 ) (1.5lbs)
        
         | riknos314 wrote:
         | Likely contents weight vs (shipping weight).
        
         | Rebelgecko wrote:
         | Maybe weight of the contents of the containers vs overall
         | weight?
        
           | pxeger1 wrote:
           | 0.5lbs is a lot of packaging
        
       | NotYourLawyer wrote:
       | This is pretty interesting. I did not realize ZnS was no longer
       | state of the art (although I probably should have).
        
       | dekhn wrote:
       | I've used similar stuff based on aluminum strontiate. It's
       | absurdly powerful. I blend it into epoxy and then pour that into
       | things.
        
         | noman-land wrote:
         | What kinds of things?
        
           | dekhn wrote:
           | My best is a glow-in-the dark Pacman and ghosts. it's a big
           | black plastic board with shapes cut into it with my CNC. Then
           | I backfilled the shapes with the appropriately tinted epoxy
           | which dried in place. Then I have a UV light pointed at the
           | board. At night, you don't see the board, just some glowing
           | figures suspended. Yellow and green work great,
           | blue/red/purple not so much.
           | 
           | I also embed LEDs into epoxy resin that's tinted, which makes
           | the whole thing glow amazingly for very long periods of time.
           | 
           | Just random stuff, really anything that comes into mind.
        
       | pprotas wrote:
       | I want to eat it
        
       | tmikaeld wrote:
       | Too bad this can't be bought in Europe, the self-glowing stuff
       | I've tried here (including tape) last only about a year, then
       | it's useless.
        
         | heeen2 wrote:
         | https://www.amazon.de/gp/product/B0114G2SZ8/ref=ask_ql_qh_dp...
         | comments by the seller indicate that it is europium doted
         | strontium aluminate - maybe some chemist can comment if this is
         | the same stuff.
        
           | tmikaeld wrote:
           | Thanks, I'll try it!
        
           | kortex wrote:
           | It's most likely the same chemical formula (so yes, "same
           | stuff"), but phosphors vary quite a bit in their quality
           | based on the synthesis conditions (maybe the "same stuff", or
           | may be better/worse quality than UN's batch).
        
         | bjornsing wrote:
         | "UltraGlow(r) powders are a new generation phosphorescent
         | material with an astonishing glow time as long as 30 hours!"
        
           | genewitch wrote:
           | and the "glow time" is only to a value of .32mCd, which is,
           | per their copy, "100x more luminescent than necessary to see
           | with the naked eye"
           | 
           | so more than 30 hours after being charge for 5 minutes in the
           | sun.
        
           | CodeMage wrote:
           | It "recharges" when exposed to light.
        
         | kyleblarson wrote:
         | What do you use it for?
        
       | notacoward wrote:
       | Strontium aluminate doped with europium has been the standard in
       | persistent phosphorescence for a while. A large part of the
       | reason I got into epoxy resin craft was to incorporate it in
       | glowing elements, so I have a _lot_ of such items. Some last all
       | night. Some - especially reds and purples - are faint and barely
       | last an hour. More recently, I 've noticed dysprosium being added
       | to the mix as well, though TBH I've never noticed any difference
       | in brightness or duration compared to stuff I could get ten years
       | ago.
       | 
       | The one thing I'd highlight (heh) for anyone trying to use this
       | stuff themselves is: be aware of its density. I have yet to find
       | a version that disperses evenly in resin; it tends to sink
       | instead. Might disperse better in glass, but I know little about
       | that craft so maybe it would be unusable for other (thermal?)
       | reasons. If it tends to sink _or_ float in any medium, such as
       | paint, color /glow will be uneven. There are ways to deal with
       | this issue, but they tend to involve extra steps. For example,
       | with resin you can pour many thin layers, but if you want to
       | avoid visible strata you have to go even further with non-planar
       | surfaces and thickeners and such. It's ton of fun, but also a bit
       | of work sometimes.
        
         | beambot wrote:
         | Care to share pictures of some of your creations...?
        
         | ridgeguy wrote:
         | Might it suspend better/longer if the particle size were
         | smaller?
         | 
         | I've ordered some, will try a little comminution to get fine
         | dust. At some point, viscosity should predominate over
         | settling.
        
           | notacoward wrote:
           | In my direct experience, grain size hasn't made much
           | difference. Also, I use several kinds of very fine
           | dusts/powders in my resin work and I've come to loathe the
           | whole category. They go everywhere at the _slightest_ puff of
           | air, stick to equipment and tools, etc. I already wear a
           | mask, but with chemical (NIOSH magenta or olive) rather than
           | particulate cartridges, so there 's that too. Of course YMMV.
           | Perhaps also relevant is that I tend to work mostly with low-
           | viscosity resins because it's easier wrt bubbles and edge
           | creep, but I've had the settling problem even with higher-
           | viscosity formulations. Maybe some day I'll hit on a
           | combination of materials and techniques that solves the
           | problem. Just hasn't happened yet. Good luck!
        
           | dandelany wrote:
           | per the docs at https://www.unitednuclear.com/glowdata.htm :
           | 
           | "Do no not grind the glow powder or try and dissolve it. On a
           | microscopic level, the glow powder works by an energy
           | exchange in its crystalline structure. These crystals are
           | very small and just appear like a fine powder. When they are
           | mixed with a clear medium as we do with our glow paint, the
           | glow powder does not dissolve, it is just suspended in the
           | medium. If you mix the powder with a medium that causes it to
           | break down and dissolve (like water), the glow will be
           | ruined. The same thing will happen if you grind the glow
           | powder. You crush and destroy the crystal matrix and the
           | energy will not be able to transfer between the glow material
           | molecules causing a dramatic drop in glow brightness."
        
       | [deleted]
        
       | jakedata wrote:
       | I wonder if the radium dial paint in my Baby Ben clock would emit
       | enough energy to activate the Europium? The original phosphor has
       | degraded to the point where it doesn't glow but it certainly sets
       | off my Geiger counter.
        
       | swayvil wrote:
       | I've used Strontium Aluminate glow powder (mixed with watergel,
       | resin). It's potent stuff. I think this europium stuff is that.
        
       | braingenious wrote:
       | I _LOVE_ United Nuclear. They have made many chemistry and
       | physics classes so much fun.
       | 
       | Here's a bit of free advice though: Do not tell a police officer
       | that you have thermite on you. Furthermore, do not explain what
       | thermite is if they don't know what it is. It is a recipe for a
       | really long day.
        
         | noman-land wrote:
         | Never heard of this site before but it has a pretty fun
         | catalog. Caffeine Soap!
         | 
         | https://unitednuclear.com/index.php?main_page=product_info&c...
        
           | layer8 wrote:
           | Not very convenient though:
           | 
           | > leave on for at least 1 minute before rinsing.
        
             | culi wrote:
             | Why's that not convenient. I usually turn the water off
             | while I apply soap and then turn it back on when I've
             | finished to conserve water. That wait time is around a
             | minute anyways. From talking to international friends this
             | seems to be the norm around the world though I wouldn't be
             | surprised if the average American doesn't practice this.
        
               | bradknowles wrote:
               | Not me. Water is on the whole time. I will move the body
               | part I'm washing out if the stream long enough to apply
               | lather, then immediately rinse it and then repeat. I
               | would be surprised if there aren't at least a large
               | minority that are at the two extremes here.
               | 
               | And caffeinated soap has been around a while, and I've
               | been using it off and on. Some are good, some are not.
        
               | layer8 wrote:
               | You'd have to wait at least a minute _after_ applying the
               | soap.
        
         | ortusdux wrote:
         | Heatgen is a new company that is selling self-heating aluminum
         | cans. As I understand it, it uses a thermite reaction as its
         | heat source. So who knows, maybe having a thermite charge in
         | your pocket might become more common!
         | 
         | https://www.youtube.com/watch?v=zSpuTwEOpOg
         | 
         | https://www.poweredbyheatgen.com/
         | 
         | https://www.highbrewcoffee.com/products/self-heating
        
           | braingenious wrote:
           | Oh dear LORD NO
        
             | vlachen wrote:
             | I've designed a lot of dumb things in my life, but that
             | beats me, hands freaking down. Can you imagine the complete
             | clusterfuck a crashed semi trailer full of these things
             | would cause?
        
           | uoaei wrote:
           | That is an objectively terrible design. The video through the
           | first link demonstrates that, if you remove the liquid before
           | activating the charge, it gets so hot it _melts the aluminum
           | jacket for the charge_. Seems then trivial to cause an insane
           | amount of destruction, even accidentally. Definitely one of
           | the more surefire ways to commit arson, especially in
           | wildland settings.
        
             | ortusdux wrote:
             | IIRC, the last attempt at self-heating cans had to be
             | recalled due to fire hazards.
             | 
             | Edit* - https://www.engadget.com/2006-05-05-self-heating-
             | wolfgang-pu...
        
             | 13of40 wrote:
             | Makes me wonder what happens if you remove the liquid and
             | replace it with more thermite.
             | 
             | Edit: Come to think of it, it might just absorb the heat
             | and do nothing.
        
         | at_a_remove wrote:
         | Tell them that you're a rail enthusiast, and start going on
         | (and on) about how they use it to weld together train tracks.
         | The more detail you go into about the trains, the more likely
         | they are to want to get away from you.
        
           | bell-cot wrote:
           | Thermite is basically a quick, low-tech welding compound.
           | 
           | Unless you actually work for the railroad, talking about
           | welding railroad tracks may trigger "he's a terrorist
           | planning to cause a train derailment" thoughts in the law
           | officer.
        
         | qbasic_forever wrote:
         | But if you do tell them about your thermite, make sure you have
         | a small stash hidden away on your person so you can melt the
         | prison bars and escape.
        
           | annoyingnoob wrote:
           | On or In? Yikes!
        
             | akiselev wrote:
             | Thermite on, ignition source in.
        
         | lief79 wrote:
         | That is begging for a story, although I'm guessing the summary
         | might be more entertaining.
        
           | aliqot wrote:
           | I think United Nuclear was Bob Lazaar's company
           | 
           | edit: yep https://www.justice.gov/civil/cpb/case/us-v-united-
           | nuclear-s...
        
             | cactusplant7374 wrote:
             | Does he still own it? I would never buy something from a
             | con artist like Lazaar.
        
         | irq wrote:
         | Sounds like an interesting story, care to share it? :)
        
           | braingenious wrote:
           | Back in the early 2000s me and a few friends were playing
           | with thermite in a parking lot, igniting tiny piles of it and
           | watching it burn into the asphalt.
           | 
           | Somebody across the street called the police and all of a
           | sudden two cop cars and a fire truck showed up. They saw we
           | were just kids and pretty much just told us to fuck off,
           | which I would have, except I had just put down a sizable pile
           | of thermite on the ground.
           | 
           | Being both a genius(moron) and civic-minded, I asked if I
           | could clean up my pile of thermite first so as to avoid any
           | danger to others.
           | 
           | Then I was asked what that is, so I happily told them about
           | how it creates extremely hot iron slag that can melt through
           | lots of things.
           | 
           | And then me and my friends were interrogated about being
           | bomb-makers, terrorists, or if we were planning on doing
           | another Columbine. They called in the local FBI (who
           | thankfully knew what we were talking about and didn't really
           | give a shit), we got a long speech about the PATRIOT act, and
           | at the end they said we're all going on "a list"
           | 
           | Ruined my entire evening and I never got to ignite the big
           | pile :(
        
       | pazimzadeh wrote:
       | What do you do with this?
        
         | jahewson wrote:
         | Use it as an additive in paint, resin, etc. to make glow-in-the
         | dark stuff.
        
         | kortex wrote:
         | Add it to anything you want to make glow-in-the-dark: paints,
         | toys, safety equipment. I know someone who produces small batch
         | silicone adult entertainment devices for sale, and the GITD
         | ones are quite popular.
        
           | hackernewds wrote:
           | This worries me as something we find out decades later having
           | cancerous or DNA altering properties
        
             | kortex wrote:
             | Doped strontium alluminate is not exactly food grade
             | (though it is considered non-toxic), but that's not the
             | orifice these devices are going in. The silicone matrix
             | retains the vast majority of the pigment, which itself is
             | fairly inert. It has virtually no bioavailability and any
             | of the micrograms of it that might slough off during a
             | session will almost certainly be exuded in short order.
        
       | pengaru wrote:
       | When you have a bottle full of this stuff, is the interior powder
       | getting charged by photons as well via propagation? Or is it only
       | the directly light-visible surface that gets charged and is
       | glowing?
       | 
       | If the former, does having a larger interior volume of powder
       | increase the glow duration, behaving as a sort of rechargeable
       | glow battery? Or does it just generate heat or more brightness
       | while lasting the same duration?
        
         | dekhn wrote:
         | only the surface of a bottle of this kind will emit photons.
         | The emission frequency and intensity is not enough to really
         | make this propagate light significantly. Instead, you would
         | suspend a tiny amount of this in a volume of transparent resin.
        
           | at_a_remove wrote:
           | Being kind of a maniac for glow in the dark stuff, this isn't
           | quite true. I've filled up flask bottles with glow gravel of
           | this variety and, after a "charge," poured it out -- the
           | interior gravel did indeed get charged. I think you would
           | need much more thickness than a centimeter or two for the
           | interiors not to get charged up.
           | 
           | (Yes, I had a bunch of bottles filled up and arranged on a
           | rope so they would glow softly during the night because I'm
           | weird like that)
        
             | pengaru wrote:
             | Since you seem to have done some experiments, what effect
             | does increasing the bottle size have on the glow? Duration
             | or brightness changed? No visible effect?
        
               | at_a_remove wrote:
               | You max out pretty fast. Most people don't understand the
               | incredibly wide (over so many orders of magnitude) ranges
               | our eyes (and ears) function over. Once you're in the
               | dark, the glow is quite visible but it wouldn't have been
               | very notable before. And so the absorb-release cycle can
               | penetrate rather rapidly. If I had to guess, with the
               | gravel, that would die off at maybe a few centimeters of
               | depth.
               | 
               | Essentially, you're getting just surface area at a given
               | brightness, despite the interior gravel getting charged.
               | 
               | With the zinc sulfides, they really did take much longer
               | to hit their max charge, although I never measured it.
        
         | genewitch wrote:
         | it emits 520nm but requires 200-350nm to activate. So the
         | outside glowing probably won't affect the inside much, if at
         | all.
        
       | deegles wrote:
       | the description says you can mix it with glaze... do they mean
       | ceramic glaze? would the glow in the dark properties survive
       | firing in a kiln?
        
         | detaro wrote:
         | The description also says: _" It can be mixed with glaze and
         | fired in a kiln to make pottery and other ceramic items. Its
         | temperature limit is about 1,200degF."_
        
           | deegles wrote:
           | ah I missed that, thanks!
        
       | rob74 wrote:
       | > _is the brightest, longest lasting, non-toxic & non-
       | radioactive, glow-in-the-dark material known_
       | 
       | Well that's a disappointment if, misled by the name "United
       | Nuclear", you were hoping for the real stuff
       | (https://en.wikipedia.org/wiki/Radium_dial)
        
         | status200 wrote:
         | They have a small section for the real stuff:
         | https://unitednuclear.com/index.php?main_page=index&cPath=2_...
        
         | akiselev wrote:
         | United Nuclear sells the real stuff like yellowcake for
         | $15/gram [1] so if you've got hydroflouric acid [2], a big
         | gaseous centrifuge, millions of dollars, and a death wish, you
         | can make weapons grade uranium too!
         | 
         |  _PLEASE DO NOT ATTEMPT THIS AT HOME_
         | 
         | [1]
         | https://unitednuclear.com/index.php?main_page=product_info&c...
         | 
         | [2] https://www.laballey.com/products/hydrofluoric-acid-
         | electron...
        
           | foobarian wrote:
           | Any idea how it is legal to ship this kinda stuff?
        
             | akiselev wrote:
             | You'd want to ship the yellowcake as HAZMAT Class 7
             | radioactive and it cannot be shipped outside the United
             | States without an NRC export license (probably continental
             | US only too).
             | 
             | The hydrofluoric acid should be shipped as HAZMAT Class 8
             | corrosive.
             | 
             | Edit: If you're asking _why_ it 's legal to sell this
             | stuff, naturally occurring uranium is over 99% U238
             | isotopes. Extracting useful U235 from it requires some
             | really nasty chemistry, insane amounts of electricity, and
             | very specialized hardware like gaseous centrifuges powerful
             | enough to separate isotopes. Buying the thousands of
             | kilograms you'd need to build a bomb would set off a ton of
             | alarm bells all up and down every major government but
             | small samples for educational or novelty purposes aren't a
             | concern.
        
         | Dork1234 wrote:
         | Full Quotes for reference " Our Europium UltraGlow(r)
         | phosphorescent (glow-in-the-dark) powder is the brightest,
         | longest lasting, non-toxic & non-radioactive, glow-in-the-dark
         | material known"
        
           | genewitch wrote:
           | the copy on the page cuts off at that last Et, though, so
           | without clicking the "MORE" button ...
        
         | RobotToaster wrote:
         | Or at least tritium, but powdering that could be difficult.
        
       | at_a_remove wrote:
       | This is far better than the zinc sulfide and friends of my
       | childhood. First off, total glow is stronger. Second, the glow is
       | much longer, almost an order of magnitude to my untrained eye.
       | Third, you can get a lot more variations on color if you're
       | willing to sacrifice glow time. The zinc sulfide of my youth came
       | in green (typically) and red (very rarely) and, if it was paint,
       | smelled bad.
        
       | Hgfyrnsjdhfh wrote:
       | Anyone knows how this relates to SuperLuminova used in watches?
       | There is always much discussion in watch forums regarding how
       | good the lume is in different watches, and this looks like a nice
       | contender.
        
       | zamadatix wrote:
       | Sounds like strontium aluminate glow powder (that's where the
       | europium doping would come into play) with a heavy marketing
       | spin. I've got some of that and it's definitely better than the
       | old zinc sulfide glow in the dark stuff most of us grew up with
       | but I'm not sure it ended up being worth buying just to see what
       | the difference was. You can get it for a fair bit cheaper than
       | this site but maybe the novelty of it coming in a box labeled
       | "United Nuclear" is worth it or maybe they do a particularly good
       | job at synthesizing it compared to everyone else.
       | 
       | In a similar vein I also went and got a ton of the most saturated
       | pigments I could find after seeing some videos about it. To be
       | honest most colors were disappointing. Definitely more saturated
       | than even a good HDR TV or monitor but not impressively so. It
       | might have been more fun in the days where having a monitor that
       | properly covered sRGB accurately was uncommon but now we're used
       | to phones with good dp3 or wider gamuts stretching things out
       | because it looks more vivid and the absolute difference between
       | that and the limit of vision is less of a leap. The ultra deep
       | non-reflective blacks are as fun as advertised though. They made
       | for less an "oh, it's a really dark object" experience and more
       | "a piece of my living room is missing and turned into an empty
       | hole" feeling.
       | 
       | Edit: While I'm throwing out chemistry related party trick items
       | I've always been a fan of element cubes and have grown quite the
       | collection now. The most fun of them all is the tungsten block
       | which is dense enough to catch you by surprise. Be careful not to
       | get a "tungsten alloy" one, it eats away at the density. It's
       | also great to just toss around/fidget with... albeit one of the
       | tungsten spheres might be better for your desk and toes.
        
         | dekhn wrote:
         | If you want that kind of effect, LEDs or lasers are your best
         | bet. The colors are intensely saturated, and absurdly bright
         | (different color-specific star LEDs on PCBs, mounted on
         | aluminum heatsink, run near the current limit for the LED).
        
         | joshu wrote:
         | What are the other pigments you tried?
        
         | aetherson wrote:
         | Where do you get the ultra-black paints?
        
           | samch wrote:
           | I like Stuart Semple's store mostly because he's anti-Anish
           | Kapoor [1]:
           | 
           | https://stuartsemple.com/store/
           | 
           | [1] https://en.wikipedia.org/wiki/Anish_Kapoor?wprov=sfti1
        
         | perihelions wrote:
         | Here's an HN thread about tungsten cubes,
         | 
         | https://news.ycombinator.com/item?id=28318754 ( _" My Tungsten
         | Cube"_, 330 comments)
        
           | eps wrote:
           | Oh, yeah, I remember that one. Got $250 lighter after reading
           | it. No regrets.
        
         | blacksmith_tb wrote:
         | I have always coveted a chunk of tungsten, but be aware that
         | there's some implication that it's a carcinogen[1] though
         | that's a bit unclear if it's actually other metals it is
         | alloyed with (in which case the purer the cube...)
         | 
         | 1:
         | https://academic.oup.com/milmed/article/172/9/1002/4283401?l...
        
           | cwkoss wrote:
           | I suspect handling a tungsten cube delivers very little
           | tungsten into your bloodstream, even if you lick your fingers
           | afterwards. I'd imagine munitions or metalshop
           | grinding/polishing generates many orders of magnitude more
           | microscopic metal dust.
           | 
           | You could always coat it in polyurethane - a clear coat
           | shouldn't diminish the impressiveness of the density.
        
         | dreamcompiler wrote:
         | I like to hand someone a Tungsten cube, let them experience the
         | weight, then toss them one of Magnesium that looks exactly the
         | same.
         | 
         | "Here, catch!"
         | 
         | They act like I've just thrown a cannon ball at them but then
         | they're amazed because it's as light as a cotton ball (almost).
        
       | wiz21c wrote:
       | If I eat it, what happens ? :-)
       | 
       | Joke aside, wikipedia says:
       | 
       | > Europium is one of the rarest of the rare-earth elements on
       | Earth
       | 
       | Maybe we should regulate its use ?
        
         | kortex wrote:
         | It's used in miniscule quantities in glow powder. It's
         | commercial use as a pigment/phosphor in display, lighting, and
         | safety equipment far outweighs its use by hobbyists.
        
       | julienreszka wrote:
       | So that's what the skin of CIA agents is made of
        
       | tohnjitor wrote:
       | I wonder if this is what goes into Luminlay. Glow in the dark
       | position markers for guitar and bass.
       | 
       | https://luminlay.com
        
       | blamazon wrote:
       | I don't need 50 pounds of glowing powder... I don't need 50
       | pounds of glowing powder... I need that money for living...
        
         | 01100011 wrote:
         | I bought something like this:
         | https://patrickadairsupplies.com/products/ultimate-neon-glow...
         | 
         | from another supplier about 8 years ago and still haven't
         | managed to use any of it, beyond just being in awe of how well
         | it glows in response to a UV light.
        
           | genewitch wrote:
           | take your UV light and a jar of peanut butter into a dark
           | room...
        
         | gwbrooks wrote:
         | I'm glad I'm not the only one contemplating poor-but-amazing
         | life choices...
        
           | tomcam wrote:
           | You definitely are not
        
         | tag2103 wrote:
         | Perhaps a smaller amount? I know the conflict... I'm checking
         | my play money kitty for exactly this. =)
        
           | knodi123 wrote:
           | lol, I bought a dozen bright tritium vials as gifts for some
           | coworkers, but I was going to deliver them in person a couple
           | of months later, so I held on to them until then. It was hard
           | to let them go!
           | 
           | Glue one to your deadbolt handle, and you can see whether the
           | door is locked at a glance, from across a dark house! Hang
           | them from your ceiling fan pulls, and no more fumbling around
           | for them in the dark! (for complicated reasons, we don't
           | control ours with the switch) Putting one on your keychain is
           | a no-brainer, but still an awesome idea! And so on...
        
       | poopsmithe wrote:
       | There is some good humor on this site. :)
       | 
       | Depending on the answer given to the quiz on the bottom of the
       | Chemistry Experiments page, visitors are directed to one of
       | Thomas The Tank Engine, Disney, or the actual safety page.
       | 
       | https://unitednuclear.com/chem_exper.htm
        
       | AdamH12113 wrote:
       | I believe this is the same stuff that makes up Stuart Semple's
       | Lit glow powder and other such glow-in-the-dark pigments. It's a
       | mix of europium and dysprosium. IIRC what makes it last so long
       | is the addition of trap states for the electrons, where instead
       | of quickly re-emitting absorbed photons they can give up a little
       | bit of energy to remain in the trap state, and are later bumped
       | back out of that state by random thermal fluctuations.
       | 
       | I tried it out on some cardboard and it's almost as impressive as
       | the marketing makes it sounds. I can hold a cheap LED headlamp
       | next to it and wave it over the surface, and it leaves a bright
       | green streak behind that glows visibly for many hours afterward.
       | It doesn't stay _bright_ for very long (I suspect it 's an
       | exponential decay), but for such a short exposure I wouldn't
       | expect it to.
       | 
       | The blue version is less impressive because you need sunlight or
       | a proper UV light source to charge it up, but it does work.
        
         | dekhn wrote:
         | By trap states do you mean "forbidden transitions"
         | (phosphorescence lasts longer than fluorescence because the
         | electrons have to go through a very low probability mechanism).
        
           | AdamH12113 wrote:
           | I honestly don't know the details; I got this from a vaguely-
           | remembered YouTube video. From some quick Googling what
           | you're saying sounds right.
        
         | aliqot wrote:
         | Doesn't Noodlers also use this?
        
       | ultrasounder wrote:
       | https://unitednuclear.com/chem_exper.htm. Cracked me up. Now i am
       | going to setup a dexters lab in my garage and blow things up with
       | my 14 year old. Right now he hates chemistry but this should
       | motivate him.
        
       | nimbius wrote:
       | ah united nuclear, purveyors of high quality reagents for the
       | discerning, jittery, sleepless grad student found in only the
       | most prestigious government watch lists and infuriatingly
       | paywalled technical journals since nineteen sixty-one.
       | 
       | Thats right United Nuclear, a beguiling reminder to mankind that
       | the entire predicate of the Iraq war could just as easily have
       | been a secret santa gift.
        
         | thebigspacefuck wrote:
         | Can someone explain what this means?
        
           | q845712 wrote:
           | it's a slightly poetic and roundabout way of saying "This
           | website will sell you some funny toys and some slightly
           | radioactive stuff [like uranium ore, i guess, from previous
           | comments]. "By the way, remember when the US invaded Iraq
           | because we claimed they had stuff which is [allegedly, maybe,
           | i dunno] remarkably similar to what you can order as a gift
           | from this website?"
           | 
           | A "secret santa" is a gift giving tradition where you pool a
           | group of people together and each person gets the name of
           | someone and buys them a Christmas gift (generally within some
           | price range) but they don't know who bought them the gift. So
           | it's an opportunity to buy joke-gifts for someone you aren't
           | particularly close to, if you happen to draw their name.
        
           | [deleted]
        
       | kortex wrote:
       | United Nuclear is quite the nostalgia bomb. My first experience
       | with them was in 2008, buying a chunk of uranium ore to trigger a
       | geiger counter to use as a true random number generator. I'd say
       | "where else can you just buy a chunk of uranium ore" but... [1].
       | Of course at the time it wasn't something you could buy on
       | amazon.
       | 
       | 1 - https://www.amazon.com/Images-SI-Uranium-Ore/dp/B000796XXM
        
       | KaiserPro wrote:
       | If you are in the UK and want glow in the dark pigment suitable
       | for the home environment, then
       | https://culturehustle.com/collections/powders/products/lit-p...
       | is a good start.
       | 
       | Its not quite as bright as superluminova (the stuff thats in
       | watches) but its cheap, easy to use and is long enough lasting to
       | be good enough.
        
       | [deleted]
        
       | meremortals wrote:
       | This site (United Nuclear) is run by Bob Lazar
       | 
       | https://search.brave.com/search?q=bob+lazar+united+nuclear
        
         | Robotbeat wrote:
         | I wouldn't expect any less. This is what the internet was made
         | for!
        
       | arethuza wrote:
       | Europium is used in Euro notes as an anti-counterfeiting measure:
       | 
       | https://www.scoopwhoop.com/world/do-you-know-why-euro-bank-n...
        
         | Yaa101 wrote:
         | Interesting article, but not entirely right.
         | 
         | The fibers are not in the note but painted on top of them,
         | neither side of the note is the same fiber wise, also they do
         | get wear with usage. The fibers on the new notes are different,
         | they are more compact and illuminate.
        
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