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glaze test for val cushing cone 5/6 stone mat, whitish base,

updated fri 23 apr 04


Alisa Clausen on thu 22 apr 04

oxidation and colorants

Glaze test for Val Cushing cone 5/6 Stone mat, whitish base, oxidation =
and colorants

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

Source: Ababi
Credited to: Val Cushing

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

50 Neph. Syenite
10 Barium Carb.
5 Frit 3134 subbed Frit J
5 Lithium Carb.
10 EPK Kaolin
15 Silica

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.

Glazes appear slightly under fired. . Can see higher areas of thicker =
glaze, for example, where it dripped. Not melted in.
Tile with Copper and the one with RIO have a better melt.

Mat, milky base. Oxides are visible but slightly muted by covering =

3.0 Copper Carb.
Mat, light green glaze with slightly darker areas where thinner.

3.0 RIO
Mat, yellow glaze.

3.0 Chrome
Mat, dark green glaze, brown where thinner. Appears under fired.

Regards from Alisa in Denmark