Cobalt

Q: I've just gotten some lovely beads that are a gorgeous cobalt blue. What I'd like to know is how do I tell if they ARE cobalt? Their pedigree is lost because they went from an estate sale to a swap meet to beader and then to me.

A: What kind of blue is cobalt blue? I can't remember. Is it the bright, true blue or more of a dark, bold color? Anyway, I doubt the beads are really cobalt since cobalt is a metal. Cobalt in its metal form would not be blue, unless they are oxidized metals. I recall from chemistry that metals only show those "colors" when they are in their oxidized states. The beads could contain oxidized colbalt which gives them their color, but the beads themselves are probably not cobalt. Malachite contains copper which gives it the green color, but it is not actually copper. If the beads are a translucent, bright, true blue, I think that they are blue onyx, which is dyed that blue color. I've also seen some dyed blue agate which would be a darker, bold blue. Many blue stones are dyed. If you want to find out what it is, I would take it to a bead store or gem expert who could tell you exactly what it is. Sounds like a question to send to Lapidary journal or to call the Gemological Institute of America (or whatever the heck it's called!) and ask. (I would suspect a more common blue stone, first, though... and isn't cobalt poisonous? Or am I thinking of something else?? I'm so confused!!!)