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glaze test for 1134c mat black, cone 6 redux.

updated thu 3 may 07


Alisa Clausen on wed 2 may 07

Source : Ceramic Arts Buyers Guide, 2007
Credited to: Patrick Horsley

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 1 hour
Shut off kiln
Note: All raw materials are measured up or down to the nearest half
decimal. Colorants or additives to a 100 gram batch are measured in percent
to the 100 gram batch.

Amount Ingredient
41 Barium Carbonate
6 Lithium Carbonate
20 Nepheline Syenite
20 Kaolin--EPK
11 Silica
2 Bentonite

100 Total

2 Iron Oxide--Red
2 Manganese Dioxide
2 Cobalt Carbonate
2 Chromium Oxide

Unity Oxide
.239 Li2O
.097 Na2O
.032 K2O
.007 MgO
.009 CaO
.616 BaO
1.000 Total

.366 Al2O3
.004 Fe2O3

1.655 SiO2
.002 TiO2
.001 P2O5

4.5 Ratio
8.8 Exp
Underfired, mat to dry, opaque, but smooth surface. Very dark brown to

Best regards from Alisa in Denmark
Note this is a redux. glaze fired in Ox. Could account for the underfired
surface (RIO)?