Monday, June 30, 2008

Upcoming raku firing

I will be breaking in my new raku kiln Thursday. It's a garbage can kiln. Can't wait.

I will be using a copper matte glaze. I have seen this glaze or variations in a couple place. Several books and the best place was in a gallery, on a little note card next to some spectacular raku vases. I've never gotten this glaze to work for me. However I think the issue has been my raku technique - firing in an electric kiln then walking the pots outside into a reduction can.

Amount Ingredient
36 Copper Carbonate
36 Copper Oxide--Black
16 Frit--Ferro 3110
8 Iron Oxide--Red
4 Cobalt Carbonate

100 Total

I make a couple changes to the original, I add 2% magnesium dioxide to encourage purples. and I am dropping the RIO by 2% as I use an iron bearing earthenware for raku.

36 Copper Carbonate
36 Copper Oxide--Black
16 Frit--Ferro 3110
6 Iron Oxide--Red
4 Cobalt Carbonate
2 Magnesium Dioxide

100 Total


I'm not sure if I am adding too much magnesium but we'll see. Raku is - from my perspective - much more difficult to develop glazes. Many more moving parts; did the pot cool too much, not enough before going into the reduction can? What is used in the reduction can, newspaper or pine needles? There are dozens of variables to take into account. Raku glaze development is much more shotgunning it while wearing a blindfold.

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