What's a fun geology fact that you know?
There are a lot of cool things about geology, but I think if I had to pick one fact to hook someone into the field, it would be that certain types of minerals can flouresce under various different wavelengths of UV light!
Above is a pretty poor quality photo from a rock museum exhibit that showcased UV fluorescence. Look at all that color!
As a good example of this phenomenon on hand, here's a piece of a kind of rock called yooperlite that I snagged recently! These rocks are most commonly found around Lake Superior in Michigan, but you can often just get 'em at museum gift shops.
Pretty unsuspecting looking rock, right? It's got that igneous granite rock sort of texture (it's actually syenite! Similar appearance, different composition), with big visible coarse grains of different minerals interspersed throughout.
Now, however, when I shine some UV light on it, you really start to see a change.
Shut off the lights, and BAM!
You've now got yourself a cool little rock that looks almost like a whole fiery constellation trapped in stone. Isn't that pretty sweet? There's a whole hidden world of color in the places you least expect it, and I think that's beautiful.
Anyways, the UV flashlight used here is around 390nm, but 365nm is generally the best to get that sodalite to pop without so much of a purple light blast over everything. This applies for a lot of other minerals that flouresce around the same wavelength as well!
If you wanted to, you could absolutely go outside and rock hunt around with one of these flashlights to see if you can find anything cool laying around, but be sure to wear appropriate eye protection and stay mindful of the local wildlife! Too much UV light can disrupt animals' circadian rhythm, and it can harm their eyesight as well if you're not careful where you point it.
With that kept in mind, however; have fun with it!
