Forty year old puzzle -- why no purple?

Q: When I was a kid and wanted to do a rainbow effect with sead beads I could never find a good, "standard-size", plain, opaque color sead bead in purple. Ideally, I would have liked red-violet, violet, blue-violet, but it always stuck in my mind that this was one color that was not to be had. The best I was ever able to do was a sad chalky pale lavender I found in tubes at a local hobby shop, literally 35 years ago. I've since learned that beads have varying prices based on the amount of gold needed to make their color. But what is behind the lack of purple in the plain opaque sead beads? Am I simply not looking in the right places? There's this little 5-year-old inside me who is still on the hunt for that illusive batch (dare I ask for range?) of nice opaque purples!

A: You are not alone in the quest for beautiful permanent purple glass beads. They do not really exist. The reason for that is permanent glass pigment is made with metallic oxides and metallic salts - mixed directly into the silicon dioxide (sand) before melting. Metallic oxides are the only pigments that can stand the heat of forming glass, and are therefore the only permanent pigments. Each metal in oxide or salt form creates it's own signature color in the glass, for instance: cobalt makes blues and blue violets selenium makes amethysts cadmium makes yellows, oranges chromium makes bright yellows, greens manganese makes pinks, violets, blacks copper makes blue-greens, reds, ruddy browns silver makes ambers, browns, gold makes true reds, pinks zinc, titanium make whites, opals The purples that are able to be produced are, by nature, fairly dull in comparison to other colors such as a gold red or copper green. It's just the nature of how glass is made. Until a way is discovered to pigment glass permanently by other means we all have to settle for dull purples. This is especially the case in opaque beads, where often a mixture of metallic oxides, such as zinc, will dull the color further. Flourine is also used to make glass opaque, but you need a vivid purple to begin with, and there just isn't one.