Dichroic colour shifts

[Gail Bunt]

Hello, after 5 or 6 years away from glass. Sold my Skutt round kiln and clamshell back then and have just started to play with my remaining kiln, a 7" shelf Paragon Caldera, and dichroic. In the bigger kilns, I only used tiny accent pieces of dichroic and didn't see any colour shifts.

In this little kiln there are wild and wacky shifts. One piece of genuine CBS dot pattern with magenta centres that did not shift in my old kilns fires orange in the Caldera (1200 1200 5). I got a bunch of thin rainbow on black from dichroandmore. Looks like CBS. Put some on a base of black, capped with clear, and ramped conservatively to top temp 1425 20. The blues were gorgeous but the rainbow magenta fired to flesh colour. Tried some different shades of rainbow capped and uncapped--shifted all over the spectrum. I don't want to use up too much more on tests.

Could lack of ventilation be a factor? A bead collar with little door that could be opened is packed away somewhere. Yes? No? At top of kiln? At bottom? Or is colour shifting just life with dichroic?

All is Sys 96.

Gail

[Lynn Perry]

Hi, Gail. You might want to take a look at this page to learn more about color shifting. Like most things, if you want it to shift, it won't, and if you don't want it to shift, it will, provided the coating doesn't popcorn or flake off the glass. Some colors and coatings are more prone to surprises than others. Some coatings are great uncapped but go very muted when covered with clear. CBS does not provide any guidance on which are which. When you purchase patterned glasses from Profusion or Duncan Dichroic, you are getting CBS coatings which have been etched.

http://www.artisandichroic.com/dichroic ... d%20colors

[Gail Bunt]

Lynn, thanks so much for the link. What a great explanation!

Gail