They come in pretty much most colors, although some are harder to find than others. Every variety of green, from forest and emerald to (harder to find) chartreuse and olive; dark blue, light blue, icy blue; turquoise or cyan; dark amber, golden amber, light amber, and a color Alan B. used to call "pilsen," and the HTF true yellow. Dark purple, medium purple, kinda HTF lavender; I have an oddball purple one I can only call grape, seriously different from the usual purple, but I don't know how hard it is to find. Colorless. Pale bottle green. Red is very, very HTF. . . and I've never seen or heard of a true orange mica.
Since I don't collect large marbles, I'll leave the size stuff to others . . .