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glaze test for leather, cone 6, oxidation.

updated thu 24 jan 02


Alisa og Claus Clausen on wed 23 jan 02

Glaze test for Leather, cone 6, oxidation.

Source: Clayart
Credited to:

All tests fired on white, iron flecked, mid-range stoneware.
Fired to cone 6 (1220c) in oxidation.

Firing ramp:
100c (212f) per hour to 600c (1112f)
150c (302f) per hour to 1100c (2012f)
100c per hour to 1220c (2228f)
15 - 30 minute soak depending on matts and glosses used.
cool down 100c per hour to 900c.
Natural cool down to 150c (approximately 15 hours)

21 Dolomite
10 Gerstely Borate
9 Spodumene
5 Wollastonite
27 Custer Spar
12 Neph. Syenite
16 Kaolin

All raw materials measured up or down to nearest whole decimal.
Oxides used on percent basis to a 100 gram batch of glaze.


Resulted in:
Base glaze is a covering white matt, very similar to the WoDo white I use
The painted lines of Burgandy stain, RIO and Cobalt oxide all showed will
under the glaze,
althought he stain should have been applied over the glaze for a better
show. The lines of oxides
have soft edges under the glaze.

The glaze is thick and white, a soft white, not a stark white. It has a
nice smooth feel and is matt without
being dry. It is almost waxy.

1 Cobalt oxide
Very similar to WoDo Blue (Lotte's Blue).
A lavendar blue with darker blues where thinner,
more pink and lavender where thickest. A lot of
nuances throughout the matt surface.

1 Cobalt oxide, 3 Rutile
A mottled light blue glaze with light green splotching.
Although the surface has a lot of color play, over all, it
has a pale blue color. Interesting mild color changes from
pale blue to pale green where thickest and from brown to
dark blue where thinnest.

5% RIO
This was the most surprising.
Resulted in an over all tan glaze with fairly bright but dirty yellow
The glaze is matt but where thickest (yellow), it has a glimmer.
I have seen RIO in many shades of tans and browns and reds, but this is
very yellow, like a summer squash.

Regards from Alisa in Denmark