I made this in a beginner glassmaking class. The sample objects I was invited to make were an egg, a spiky thing or a Christmas ornament. I had noticed a wave-shaped, blue-and-white object in the store, and asked if I could make something like that. So the instructor and I started with a glass glob on a pipe, coloring it in several stages with shards of glass in green (copper or iron), blue (cobalt) and white (titanium), then bending and rippling it while molten.
A fun experience, though much shorter than the blacksmithing one.