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glaze test for oxides under chappel's semi gloss, cone 5, ox.

updated sun 17 nov 02


Alisa Liskin Clausen on sat 16 nov 02

Glaze test for oxides under Chappel's Semi Gloss, cone 5, ox. =20

Glaze tested on white midrange stoneware fired in electric oxidation to =

Source: John Hesselberths's website
(reintroduced to me by Charles Moore)
Credited to:

Firing ramp:
100c p/h to 600c (212f - 1112f)
150c p/h to 1100c (330f - 2012f)=20
100c p/h to 1220c (212f - 2228f)
cool down max. per hour to 1100c=20
cool 80c per hour to 800c
shut off kiln

45.7 Kona F-4 feldspar
15.2 Silica
12.7 Talc
12.9 Gerstely Borate
9.0 Dolomite
4.5 EPK
1.0 Bentonite

Note: All raw materials are measured up or down to the nearest whole =
decimal. =20
Colorants or additives to a 100 gram test batch are measured in percent =
to the 100 gram test batch.

Forsahmmer Feldspar for Kona F-4

Clear semimatte glaze with a satin feel. Like Charles description, it =
looks like vellum. Turned slightly yellow on my clay body.
All oxides, Cobalt, RIO, black stain, Chrome and Ochre, showed straight =
edges as painted. However, glaze covered the oxides enough to let the =
painting show through, but the colors were virtually indistinguishable =
from each other. Otherwise a well covering, good feel, semimatte glaze.

Regards from Alisa in Denmark