Vlasovite, with agrellite and uranyl-activated unknown - Kipawa Complex, Témiscamingue, Qc, Canada
Shown here is a nice specimen of vlasovite, a rare fluorescent mineral found only in a few localities around the world, along with agrellite and non-fluorescent eudialyte (two other rarities), plus some unknown uranyl-activated green fluorescing mineral. While not being the specimen with the best coverage I've seen, it's still a quite aesthetic example from this locality; and the gemmy red eudialyte makes it look pretty good in daylight too. Shown here fluorescing under SW, then MW, LW and in visible light.
The specimen overall is definitely at its best under SW; but the MW response is also quite good. The LW response isn't impressive; but since pictures of the LW fluorescence of agrellite and vlasovite (both a weak orange under LW) are rarely posted online, I thought it's a good idea to include it here.
Size: 8,3 cm X 6,5 cm X 3 cm
Shortwave UV response
Under this wavelength, both the vlasovite and the uranyl-activated green are weaker than under SW, but the agrellite is at its best.
Longwave UV response
Specimen shown in visible light. While the agrellite and vlasovite are quite boring under white light, the eudialyte is really beautiful.