Yes, a Rainbo, they come in just about every transparent color you can think of, some more common, some VHTF, a good marble to collect, you'll never reach the end of Rainbo color combinations or variations, BTW Nice mib Adam
If there is transparent clear base w/ whispy white strands running through it besides the opaque red and green, yes. I'm no positive from your pix but I think I see some trans. clear ?? Your first pic would be the one to enlarge if you can. A retake would be ideal ??
Both Popeyes Phil Thomas used to make custom boxes from hardwoods, been doing it for years, probably one of the best their is, I bought several from him.
CUSTOM BOX PIX LINK :: https://marbleconnection.com/topic/27039-new-boxes/#comment-232901