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glaze test for cooper 218 cone 6, oxidation

updated thu 3 may 07


Alisa Clausen on wed 2 may 07

Glaze test for Cooper 218, Cone 6, Oxidation

Source: Lili Krakowski

Credited to:

Fired on mid fire white stoneware

Firing ramp with an electric controller is:
100c p/h to 600c (212f - 1112f)
150c p/h to 1140c (302f - 2084f)
80c p/h to 1220c (176f - 2228f)
15 min. soak
cool down max. to 900c (1652f)
Hold 30 minutes

Shut off kiln

Colorants or additives to a 100 gram batch are measured in percent to the
100 gram batch.
Substitutions in this test: Frit 3134 subbed with local Boron Frit,
Feldspar used is Forshammer, Boron Frit is subbed for Gerstley Borate. All
substitutions are done not by Mol. Wts., but gram for gram.

Amount Ingredient
36 Feldspar--Custer
9 Whiting
22 Dolomite
5 Bentonite
28 Silica

100 Total

10 Rutile

Unity Oxide
.051 Na2O
.1 K2O
.3 MgO
.549 CaO
1.000 Total

.184 Al2O3
.006 Fe2O3

2.383 SiO2

12.9 Ratio
7.1 Exp

Semi mat, opaque glaze. Surface overall is a pale grey white, with a
mottled Rutile beige/pink blush throughout surface.

Best regards from Alisa in Denmark