I just discovered WIKIPEDA..I know I know...I'm behind the times.
So I copied an article about Aurora Borealis beads and thought it might be interesting.
I hope you enjoy it.
Aurora Borealis Aurora Borealis (AB or A/B) is a light reflecting finish applied to the exterior of a bead of any shape or size or material. Other names a bead glossary may have for AB-type finishes are iris, oil slick, or rainbow. An AB finish on a clear glass bead can indeed appear as a rainbow; on beads of color, it is more subtle but highly reflective. The real Aurora Borealis, or Northern Lights, is a fabulous color display in the night sky caused by the interaction between the solar wind, the Earth's magnetic field, and the upper atmosphere. If you've never seen the Northern lights, log on to Michigan Tech's long list of Aurora Borealis websites. The image, courtesy of NASA, is a photo of one of Jupiter's moons experiencing an Aurora Borealis. It looks very much like the luminescence of a rainbow AB bead. Click on the image, courtesy of NASA for provocative photos and explanations.