Finally got up the nerve to pop the top!!

This is a 20" Enhance Liquidteck Clear glitter lamp which needed some help badly. The liquid was dingy and the cap was corroded. Worst part was the decorative cap, which had been jammed down onto the globe somehow, and was also crooked, which had dented it and left a few creases and dings. It was the dickens to remove and will need to be straightened out, since I doubt I can find an extra cap anywhere.

There is also a "middle cap" which appears to be a heavy bakelite plastic which just sat under the decorative black one, serving what purpose, I don't know. Notice the hole in the top and the ribbing around the outside. There are no threads at all inside it. Under this middle cap was the dreaded white metal cap, that looks like a baby food jar cap, but only about a quarter inch thick. I used a small flat head screwdriver to pry it (gently) off. Then just dropped one drop of McCormick Blue Neon food coloring into it while running and it turned a lovely color of sort of teal blue. One drop was plenty enough. Now I have to get that white metal cap back on, sealant needed here, and hopefully it won't leak! I'm stoked and ready to experiment more now!! Thanks goes out to Jack for his much needed advice!!

Before, After and cap pics: