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glaze test for clear ^6, ox.

updated sun 2 mar 08


Alisa Clausen on wed 27 feb 08

Glaze test for Clear ^6 ox.

Source: Clayart

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.
Standard Substitutions in all tests:
Local Boron Frit is used for Frit 3134
Forshammer (a half and half Potash and Soda spar) is the only Feldspar used
Local Boron Frit is used for Gerstley Borate
All substitutions are done not by Mol. Wts., but gram for gram.

Recipe Name: Clear ^6
Cone: 6 Color:
Firing: Surface: Glossy
Amount Ingredient
51 Nepheline Syenite
22 Gerstley Borate--1999
14 Wollastonite
8 Zinc Oxide
3 Titanium Dioxide
100 Total

Unity Oxide
.225 Na2O
.061 K2O
.016 MgO
.456 CaO
.242 ZnO
1.000 Total
.33 Al2O3
.2 B2O3
.001 Fe2O3
1.755 SiO2
.092 TiO2
5.3 Ratio
8.7 Exp

Comments: gloss, transluscent, crazed

John Sankey on sat 1 mar 08

Just to note that this is credited to Richard Zakin and is already
in the database as Zakin Clear. It does indeed have expansion on the
high side, but works perfectly if mixed as in the original, which is
fluid and thin (see The JM 169 frit
that Alisa subbed for the borate has a lot more silica, which would
raise the maturing temperature.
John Sankey

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