[Griffith]

I am having inconsistant results firing cone 6 blues and greens. Anyone know why these sometimes fire to brown instead of pattern blue or pattern green?

[weeble]

HMmm, more information? Type of clay and type of glaze are rather critical bits of information in figuring out your problem.

I've been using commercially available Laguna clay and many different commercial glazes fired to cone 5 in an electric kiln for years and I've never had blue or green go brown.

[clay lover]

I agree, more info. But...if too thin, many glazes come out brown. severe over firing can also produce this.

[bciskepottery]

When you layer two glazes, you create a new, third glaze. Sometimes the components of the glazes you layer mix together nicely, and give you good results. Sometimes, something in one glaze may not play well with the ingredients of the other glaze . . . resulting in those teachable moments we all have (but would prefer not to have). Look at what is in both glazes and make sure you don't have the latter case. My guess is the two do not play well together, in which case you'll need to find a more complimentary set of blues and greens.

[Idaho Potter]

Using commercial glazes compounds the problem, because you don't know what ingredients make up the glaze. I recently had this happen to me using Snowflake White and Dark Green--both from Laguna. I also tried Matte White and the Dark Green. Each were okay by themselves, but where they overlaid one another, brown (like weak coffee). Now that I know that, I will probably find sometime down the road it will be just what I want.

[SmartsyArtsy]

There is another thread dealing with a similar issue. http://ceramicartsda...ar-satin-glaze/

The problem is often Zinc but in my case there was no zinc, and further explanation has yielded no answer. Read through that link. I have been very busy with sales and shows, but I intend to follow up next month.