Alisa Liskin Clausen on sat 4 nov 06
Glaze test for Brian Gartside Base, cone 6, ox.
Source: Brian Gartside, New Zealand
Credited to Brian Gartside http://www.gartside.info/homepagesouthx.htm
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
Recipe: by volume
Frit 3134 4 parts
EPK Kaolin 4 parts
G-200 Feldspar 2 parts
Silica 2 parts
Talc 1 part
Whiting 1 part
Water 16 parts
Colorants or additives to a 100 gram batch are measured in percent to the
100 gram batch.
The glaze base produced a transparent gloss, which unfortunately, where
double dipped and thickest, crazed on my clay body. However, many of the
colored test did not craze, or only where thick. Application could also be
a key in the success of this glaze on my clay body. However, next test, I
will test this parts recipe more precise and see if the big batch I made
was, perhaps, not precise enough. However, the base colored very well and
as Brian has used this base in over 20 years, I am sure I can adjust it to
fit my clay.
I think the sheer spectrum of colors that resulted from this base, gives a
good incentive for those who seek not to have many, many glazes in their
studios, but rather a couple of bases they can color. Personally, I think
that is an excellent idea, as I too, have two to three bases that I use
regularly, and color as I need them. I usually have a few kilos dry glaze
of each base, so that I can mix smaller amounts with coloring oxides. This
base liked RIO, Titanium and Rutile, giving some very exciting color
responses. Nr. 8, 12 and 13 all showed very nice breaking contrasts in
color. Nr. 13 yielded an especially beautiful Tenmoku glaze, with dramatic
Here are the results of these tests.
Please go to
to see photos of the tests. I recommend double clicking on the photos to see
the best details of the glaze surface, as there are many with interesting
shells, furs, streaks, and color clarity and depth. The glazes that showed
no crazing have only been evaluated by my eyesight in the light.
Transparent gloss. Crazed where thickest.
2. 1 Cobalt Ox.
Translucent vivid blue.
3. 2 Cobalt Ox.
Translucent darker vivid blue, .
4. 1 Cobalt Ox., 3 Rutile
Translucent brownish green ground, with vivid opalescent blue areas
where thickest. .
5. 1 Cobalt Ox., 3 RIO
Translucent, brownish green glaze.
6. 1 Cobalt Ox, 5 Ochre
Translucent, dark blue glaze with a slightly "black denim" cast.
7. 3 Rutile
Semi translucent glaze, creamy beige to yellow color. White and
slightly opalescent shell over ground color.
8. 5 Rutile
Opaque, gloss, soft white glaze, breaking beige. The glaze appearance
goes from white where thickest, to a breaking color where
the thick white disperses to tiny bubbles of white, which gives a fur
appearance, and then finally all of the white disappearing to yield a beige
where it is at it's thinnest.
9. 3 Rutile, 3 Copper Carb.
Translucent, sage green (muddy celadon) gloss, breaking clear.
10. 3 Copper Carb.
Translucent, medium green, gloss. Many translucent areas without much
color in ground green color. Crazed.
11. 6 Copper Carb.
Translucent, medium green ground, gloss, with thicker areas showing an
iridescent surface over a darker green gloss.
12. 1 Cobalt, 4 Rutile, 2 RIO
Opaque, light blue gloss glaze with some yellowish streaking where
thickest, over a brown ground with a green cast, where thinnest and
Glaze breaks with a dramatic color contrast from brown where thinnest,
to a smooth, milky blue where thickest.
Note, these colorants are the same as Floating Blue or Blue Hare.
13. 10 RIO
Opaque, gloss glaze that is a tenmoku color. Overall, the glaze is a
deep black, flushed with brown where thinner or breaking.
The brown areas have broken and dispersed edges as it they lead into
the thicker black areas.
14. 5 RIO
Semi opaque, gloss glaze. Overall dark brown color where thickest,
lighter brown similar to above where thinner. Breaking contrast is
not as dramatic as above.
15. 10 Ochre
Translucent gloss, glaze. Greenish yellow in overall cast. Crazed
where double dipped.
16. 10 Tin Ox.
Opaque, gloss, soft white glaze.
(17. 5 Tin Oxide)
18. 10 Zircopax
Opaque, gloss white glaze. Not as white as Tin, but slightly creamy
19. ( 5 Titanium Diox.)
20. 10 Titanium
Semi opaque to translucent gloss, glaze. White where thickest,
giving way to a yellow ground under the white, where thinnest.
Breaks, in high contrast to the white areas, a yellow-green to orange
21. 5 RIO, 5 Titanium
Semi opaque, gloss glaze. Medium brown ground where thinnest, fur
like beige and green where thickest. Breaks brown.
22. 3 Nickel
Semi opaque, gloss glaze, dark caramel in color. Where slightly
thicker, glaze is more fluid and pools to a bluish green fur like surface.
23. 1 Tin, 1 Cobalt
Translucent, gloss dark blue glaze. Glaze crazed where thickest.
24. Pink Stain
Translucent, gloss glaze. Pink stain visible in glaze's overall
color. Glaze crazed where thickest.
25. 2 Cobalt Ox., 5 RIO
Opaque, gloss glaze. Black where thinnest, begins to turn browner
26. 2 Nikkel, 10 Zink
Opaque, gloss glaze. Medium caramel ground color where thinnest.
Signs of bluish-green pooling where thickest.
Regards from Alisa in Denmark