Saturday, September 10, 2011

Blue Celadon cone 10 [Pinnell Blue Celadon (rev. 1)]

Blue Celadon cone 10

24.75 Custer Feldspar
34.65  Silica
19.80  Whiting
  9.90  Grolleg
  8.91  Calcined Grolleg
  1.98  Barium Carbonate

Add 1.0 Tin Oxide
        0.5 synthetic iron oxide

Fire in the R1 cycle in my book or reduction from 010 to peak.

I took Pete Pinnell's Celadon and since it crawled on me a bunch, I calcined half the Grolleg and came up with this.



Josh Brown said...

You guys still use barium?

John Britt said...

Yes. That glaze has very little barium carbonate and I had it tested three times with very low release levels. You can use a liner without the barium if you like.

Pete Pinnell said...

Thanks, John! That's a good idea. I've always thought the clay content was a bit high.

John Britt said...

It is a great glaze but I just got irritating crawls intermittently on the rims.

Not sure how this will work but it was a nice blue, not as transparent.

I will have to fire it a bunch more to see how it performs.

Carolanne Currier said...

Hey John- Why synthetic RIO? Any advantage in this recipe over Spanish RIO? Also, is you sample on Helios?

John Britt said...


The synthetic is the most pure. 99.0% vs 86% , 92% etc. Sample is Helios (grolleg ).