Potters & Sculptors - Making Rock from Mud
I am not certain of the origin of this glaze but I got it from the Prince Albert Arts Center and I believe they got it from the Saskatoon Potter's Guild.
Custer Feldspar 22
Gerstley Borate 22
Neph Syen 22
Titanium Diox 2
Red Iron Oxide 3
Copper Carb 4
I sprayed the glaze, applying continuously and working around the piece until the glaze started to run. This gave me a somewhat thick coat which fired to a nice glossy brown with very funky green spots.
What did you bisque at after the glaze fire? 06?
Usually it is a fast ^06. If I have something in with a real bisque, then it goes to ^04 on a slow bisque. It is the time spent up around 900c that allows the RIO to crystallize into the red that you see. I normally do a 45-60 min hold @ 962c on the way down & that helps, but putting it back in the bisque draws out even more red. jhp
This is Frogskin on porcelain fired to ^6 with a very slow-cool from 1,800 F to 1,500 F at 50 F per hour.
I just applied "Clear Base Blue" on iron-rich Amador clay and pulled out some pieces which were golden brown without a hint of blue or green. On this white clay tile the golden brown is clearly visible only on the breaks in surface texture.
3.0% Red Iron Oxide
1.0% Cobalt Carbonate
0.8% Copper Carbonate