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glaze test for white crackle fired to 1220c ox.

updated fri 14 jun 02


Alisa Liskin Clausen on thu 13 jun 02

Glaze test for White Crackle fired to 1220c. ox.
Source: The Potters Manual, Kenneth Clark
Attributed to

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

Firing ramp:
100c p/h to 600c (212f - 1112f)
150c p/h to 1100c (330f - 2012f)=20
100c p/h to 1220c (212f - 2228f)
cool down max. per hour to 900c (1652f)
hold for one hour at 900c
shut off kiln

80 Soda Feldspar
10 Kaolin
10 Whiting

Note: The example was fired to 1275 and showed large crackling, like a =
raku firing. =20
The fired pot was refired after the cracks were filled with Iron oxide =
to get a smooth surface.

All raw materials are measured up or down to the nearest whole decimal. =

Colorants or additives to a 100 gram test batch are measured in precent =
to the 100 gram test batch.

Substitutions: None

Results: Test was underfired and no crackling. A smooth white matte. =
If someone tries this test higher,
would appreciate hearing results.

Regards from Alisa in Denmark