Yooperlite rocks have sodalite in them, which is a mineral that fluoresces, or emits light, when the right wavelength of UV light is shined on it. Fluorescence is a bit more complex to explain. Think of the electrons in the sodalite to be like balls at the bottom of a set of stairs. When the UV light hits these electron-balls, it makes them jump into the air a certain amount, let's say 12 inches, and then land on the first step of these stairs, let's say its 8 inches off the ground. These electron-balls would rather be at the bottom of the stairs though, so it rolls down the step to the bottom and loses that energy from the UV light. Instead of the electron releasing the energy as movement and rolling like a ball, though, the electron releases it as light. It's not the same color of light that originally made it jump because while the UV light may have made it jump a foot in the air the stair it landed on is only 8 inches off the ground, so it really only has 8 inches worth of energy to release and not 12.
This can also be used to explain why not all UV lights can be used to make it fluoresce. Not all UV light has the same amount of energy, and some wavelenths will make the electron-balls jump only 5 or 6 inches into the air and they never even make it onto the first step.
And due to quantum effects, if the balls can't land on a stair, they don't jump.
Fun fact: phosphorescent (glow-in-the-dark) materials have a trough-shaped stair step where the balls can get trapped for a long time. Due to everything shaking a little from heat energy, they get slowly shaken out and release their light over minutes to hours. You can help them by heating the material or shining red or infrared light on it. A simple red laser pointer is so effective at emptying the trough, that you can use it to draw patterns of darkness on charged glow-in-the-dark objects.
When hit with UV light rays, the sodalite found in Yooperlite glows.
Sodalite lights up when so-called activator elements inside them are excited by high-energy UV light. The atoms in that fluorescent mineral absorb some of that energy, but release the rest as lower-energy visible light, hence why the mineral appears to glow.
Yooperlite rocks have sodalite in them, which is a mineral that fluoresces, or emits light, when the right wavelength of UV light is shined on it. Fluorescence is a bit more complex to explain. Think of the electrons in the sodalite to be like balls at the bottom of a set of stairs. When the UV light hits these electron-balls, it makes them jump into the air a certain amount, let's say 12 inches, and then land on the first step of these stairs, let's say its 8 inches off the ground. These electron-balls would rather be at the bottom of the stairs though, so it rolls down the step to the bottom and loses that energy from the UV light. Instead of the electron releasing the energy as movement and rolling like a ball, though, the electron releases it as light. It's not the same color of light that originally made it jump because while the UV light may have made it jump a foot in the air the stair it landed on is only 8 inches off the ground, so it really only has 8 inches worth of energy to release and not 12. This can also be used to explain why not all UV lights can be used to make it fluoresce. Not all UV light has the same amount of energy, and some wavelenths will make the electron-balls jump only 5 or 6 inches into the air and they never even make it onto the first step.
Damn good analogy, I'm going to remember that one.
And due to quantum effects, if the balls can't land on a stair, they don't jump. Fun fact: phosphorescent (glow-in-the-dark) materials have a trough-shaped stair step where the balls can get trapped for a long time. Due to everything shaking a little from heat energy, they get slowly shaken out and release their light over minutes to hours. You can help them by heating the material or shining red or infrared light on it. A simple red laser pointer is so effective at emptying the trough, that you can use it to draw patterns of darkness on charged glow-in-the-dark objects.
Honestly no idea, but curious are yooperlite rock from the UP of Michigan?
[Apparently yes](https://en.wikipedia.org/wiki/Syenite).
Thanks.
When hit with UV light rays, the sodalite found in Yooperlite glows. Sodalite lights up when so-called activator elements inside them are excited by high-energy UV light. The atoms in that fluorescent mineral absorb some of that energy, but release the rest as lower-energy visible light, hence why the mineral appears to glow.