Yes, it will of course absorb or reflect the red light like any stone would, but to "charge" its luminiszence you need at least green light - blue works great.

Yes, it will of course absorb or reflect the red light like any stone would, but to "charge" its luminiszence you need at least green light - blue works great. That is, why you never could charge your watch dial with incandescent light, but any white LED will work great because their light usually contains a lot of blue light. Fun fact: though it is calles "phosphorescence" all those colors don't contain any Phosphor, that Phosphor isn't phosphorescent :p An error in early naming.