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glaze test for berry rust ^6

updated thu 28 feb 08


Alisa Clausen on wed 27 feb 08

Glaze test for Berry Rust

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: Berry Rust
Cone: 6 Color:
Firing: Surface: Semiglossy
Amount Ingredient
27.3 Silica
18.2 Kaolin--EPK
18.2 Nepheline Syenite
9.1 Dolomite
9.1 Gerstley Borate--1999
9.1 Talc
9.1 Bone Ash
100.1 Total
9.1 Iron Oxide--Red
Unity Oxide
.099 Na2O
.029 K2O
.34 MgO
.533 CaO
1.000 Total
.335 Al2O3
.097 B2O3
.004 Fe2O3
2.574 SiO2
.002 TiO2
.079 P2O5
7.7 Ratio
6.1 Exp
Comments: Semiglossy, smooth glaze. DArk brown and rust ground with dark
cream and greenish pooling on surfaces, overall.

Sent from John Post, other versions from
Carol Tripp, Craig Martell