Potters & Sculptors - Making Rock from Mud
Sometimes white clay can flash orange in a wood firing.
that makes sense. thanks.
It looks like a typical copper, high barium carbonate matt.
A high sodium glaze will flash orange like this (the soda in the glaze interacting with the iron in the clay body) even in oxidation. Pinnell's weathered bronze green does this but it is not similar enough in other aspects. There are a couple of glazes close to this in color in the "Glaze Recipe Sharing" document in the FB group "Ceramic Recipes". Perhaps if you took one of those recipes and replaced the feldspar with Neph Sye...
^6 Oxidation Chun Green (I would add 5-10% Tin or Zircopax to get the opaque look). .
F-4 Feldspar 38
Zinc Oxide 12
Ball Clay 6
Celadon: copper Carbonate 1-2%
Donna Kat---saw in your post about a FB group named Ceramic Recipes??? how would One join this group?
Replacing the potspar with Neph sy will affect the firing range, because the Neph Sy has a stronger melt. It's balance of alumina and silica is different than a potspar and may affect the outcome in other ways as well.
Ian Currie has a barium looking glaze for cone 6 that looks a lot like the glaze in question and that may be worth a test. His glaze looks like a typical Barium matt, copper blue, but without barium. I have that glaze and recipe posted on my web site in one of the cone 6 test tile pages.http://www.shambhalapottery.com
Just hit technical links on the home page, and from there select the glaze pages.
Here's the late Ian Currie's recipe for a cone 6 matt glaze which mimics a traditional, copper blue barium matt usually seen at cone 10. With the colorant additions as shown, it will give a much deeper brighter blue. But if you try a variation and only add 1% copper carb, you might just get a color similar to this. On my web page, in the cone 10 glaze tests section, you can see a Carlton Ball barium copper matt which looks exactly like this glaze. It only has 1% copper, no iron, no cobalt. It's a Neph Sy, barium, copper, kaolin, silica recipe which I have listed on that page.
#7329 Brilliant Blue
8.9 Soda Ash
8.0 Ferro Frit 3134
37.5 Nepheline Syenite
2.4 Lithium Carbonate
17.7 Strontium carbonate
A: add 3% Copper Carbonate 0.2% Cobalt Carbonate (this will be a deeper, richer color; but trying just 1% copper and eliminating the cobalt , you could probably get this.
Since a picture is worth a thousand words, that 2nd tile from the left is the Carlton Ball cone 10 Barium, copper matt that I have on my web site. The tile to the right of it is also a copper, barium, matt - a Vivika Heino recipe.
Sorry, missed this post. On FB just do a search for Ceramic Recipes and it should come up. I can give a link but I am not sure it will work. http://www.facebook.com/?ref=logo#!/groups/disisdkat/?bookmark_t=group - then just request to join. It is an open group but you still have to make the request for some reason
It is really nice to see you posting again June. Wonderful tiles as always.
May I add this comment to the Ceramic Recipes Group? It is the type of information the page needs.