Lava..?
could work with a solid color
Jars of various liquids..?
to be fair, it still would look like a colored jar but also to be fair, maybe
Muddy water..?
agh i thought he was banned alreadymaybe
Stained glass..?
relatively obscure but fair enough
Fantasy things..?
..uh?
-snip-
They just look too similar... 
the only reference i spot is that we both have four columns of different shades of colors. these colors aren't nearly even the same, and they're not in the same order, either.
