Europium UltraGlow Powder – Green
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.<p>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.<p>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.