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glaze test fortouchstone red, cone 6,

updated fri 13 sep 02


Ron Roy on thu 12 sep 02

ox. plus other colorants to base.

Expansion low when red iron left out - OK with iron for most bosies - low
in alumina - so soap make attack this glaze - I think someone once said of
this type of glaze - don't glaze soap dishes with it - Louis Katz I thnk it

Make two tiles - leave one in the dish washer forever - compare them every week.


>Touchtone Red, cone 6, ox. plus other colorants to base.
>Glaze tested on white midrange stoneware fired in electric oxidation to 1220c.
>Source: Clayart
>Credited to:
>Firing ramp:
>100c p/h to 600c (212f - 1112f)
>150c p/h to 1100c (330f - 2012f)
>100c p/h to 1220c (212f - 2228f)
>cool down max. per hour to 1100c
>cool 80c per hour to 800c
>shut off kiln
>32 Gerstley Borate
>30 Flint
>20 G200
>15 Talc
>5 EPK
>15 RIO
>Note: All raw materials are measured up or down to the nearest whole
>Colorants or additives to a 100 gram test batch are measured in percent to
>the 100 gram test batch.
>Borax frit for Gerstely Borate
>15 RIO
>Gloss glaze with many color nuances. Rust brown base with streaking in
>darker browns and slightly green browns. Edges have a bluer nuance. Some
>areas under surface are honey brown. Where very thick, the glaze ran in
>large drips. Moved and pooled where very thick, but otherwise stayed
>where dipped.
>5 RIO
>Semi matte glaze that is yellowier where thicker, browner where thinner.
>Many nuances, did not move.
>10 Ocher
>Overall yellowish glaze where thicker, shiny. Where thinner, browner and
>matter. Where very thick, it crazed.
>3 Cobalt Carb.
>Lavender semi matte glaze where thickest, bluer where thinner.
>3 Cobalt Carb. + 5 Rutile
>Medium green semi gloss base with bright, cornflower blue crystals where
>Lovely contrasts.
>3 Cobalt Carb. + 5 Rutile + 5 RIO
>Similar to above, but some movement where the edges of glaze are dark
>blue. Glaze is more fluid, instead of distinct crystals like above,
>the lighter blue is in streaks.
>Regards from Alisa in Denmark
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Ron Roy
15084 Little Lake Road
Brighton, Ontario
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513