irredescence

[glassgirl55]

I once saw glass blown plates that were irridescent and was told that this was accomplished by using a type of hair spray. Does anyone know anything about how one could do this?

[Morganica]

Iridized glass is usually made by spraying a tin-containing solution (stannous chloride) on very hot glass--it evaporates and leaves a fumed-on coating. Stannous chloride is toxic, so I doubt you'd want to spray it on your hair.

The iridescent appearance comes from metallic salts in the coating, and there are other {metal name}{something}{chloride} solutions you can use as well. The only one I've heard also used that way is titanium tetrachloride, but there are probably others.

Glassblowers can obtain iridescence either by spraying a solution on the glass or, more often, by simply reheating the glass in a reducing atmosphere (i.e., removing some of the oxygen in the gloryhole, usually by tossing in a bunch of crumpled-up newspaper). That brings the metallic salts to the surface of the glass, causing the irid effect.

I'm not sure what would be in regular hairspray to do this. I'd be very cautious about schpritzing it into my hot kiln, though--if the kiln is hot enough to fume the hairspray, it might also be hot enough to catch fire. Ever see someone use a can of hairspray as a blowtorch? http://www.youtube.com/watch?v=xvH9FLiA3z0 I wouldn't want that to happen by accident.

[Lauri Levanto]

Hairspray iridescent sounds to me like vaporware.
Has anyone tested lustres that are used in porcellain painting?
-lauri

[Cheryl]

There are lots of artists who've done work with the china painting lustres on glass for years - Higgins for example, and Avery Anderson. I have found them increasingly difficult to find, especially halo lustre. They work great on glass.