Helium Moss Brick

It cycles through the whole color range instead of settling anywhere, so a large surface of it never looks the same twice. That is the appeal and also the problem, since it will fight any fixed color scheme in the room. Use it as an accent strip or give a whole area over to it.

Unlike the other glowing moss bricks it stays at full brightness outside the world too. Sitting on the ground as a dropped item or mounted in an Item Frame it keeps glowing, which makes it a tidy permanent lamp for a display shelf where a torch would look wrong.