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glaze test for em. cooper blue curdle on jade, cone 7-9, ox. or redux.

updated fri 4 feb 05

 

Alisa Clausen on thu 3 feb 05


Glaze test for Em. Cooper Blue Curdle on Jade, cone 7-9, ox. or redux.

Glaze tested on white midrange stoneware fired in electric oxidation to =
1240c.

Source: Bonnie Staffel
Credited to: Emmanuel Cooper

Firing ramp:
100c p/h to 600c (212f - 1112f)
150c p/h to 1100c (330f - 2012f)=20
100c p/h to 1220c (212f - 2228f)
5 min. soak
cool down max. to 800c
Hold 1 hour
Shut off kiln

Recipe:
40 Kona F4 subbed Feldshammer, a blend of Potash and Soda ash
18 Cornwall Stone
18 Whiting
4 Zinc Oxide
20 Kaolin

ADD
5 Rutile
2 Copper Carb.

Note: All raw materials are measured up or down to the nearest whole =
decimal. =20
Colorants or additives to a 100 gram test batch are measured in percent =
to the 100 gram test batch.

Results:
A mat glaze, tan ground with a green cast, speckled with dark blue and =
green.

Regards from Alisa in Denmark