That's neat, I'm about to take a course in Geology, so I'm sure I'll learn about the interesting ways lasers can be used there as well.
I just joined the Astronomers group, and I just ordered a blue laser, so I'm out to a good start.
Hey, that's neat, perhaps later you could start a group for any rocks/minerials that might fluorcese some under a 405nm laser (I think there should be at least some if I remember reading right from what others said).
I'm finding out geology is especially interesting when you see how neat some of the rock and minerials fluorcese under shortwave UV, there are web sites online with photos.
You'll find out that while violet lasers might be good for a limited number of things as far as getting them to fluorcese, (and I am glad I did get a violet laser), many things like a majority of the rocks and minerals that fluorcese need shortwave (254nm) light to do so, and the violet lasers are 405nm which is just outside the longwave UV spectrum which I believe goes to up to 400nm, but 405nm is still close enough to cause some things to fluorcese. (some rocks/minerals fluorcese under longwave and midwave UV but I read that a majority need shortwave UV)
I'm not sure if there are any shortwave UV (254nm) lasers, but if so they are likely very expensive, even the shortwave LEDs that are available are very expensive and don't put off much power for the cost.
For affordable shortwave with current technology you really need the shortwave UV fluorescent tube type of lights, and even those can be fairly pricey, the lowest cost one of those I have seen so far is about $35.00 but it is a 4W portable entry model for beginners, but it does come with interchangable tubes for both longwave and shortwave UV, I recently ordered one from
UVTools LLC. and am waiting for it to arrive. (for really serious rock/minerial hunters that can afford it can pay from around $150 and up for more powerful above entry level units)