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cone 6 chit chat (glaze test results)

updated sun 31 mar 96


Michelle Lowe on thu 14 mar 96

Tested some clears last week.
On B-mix clay (white stoneware)
Test tiles were little bowls with a brush mark of red iron oxide and
another of a blue underglaze (Duncan).

Fired in my electric kiln to cone 7-ish, with a one hour soak at the end.
I found most of these clear recipes on the CeramicsWeb, either in the
database or the clayart archived glazes by searching for the keyword
"clear" and/or by browsing the cone 6 recipes. There is a search by glaze
name, so will post these. If anyone has trouble finding the recipes, email
me privately and I'll post them to you.

and now...for the results...

I. oops, no name for this one, but it's color: Semi-opaque Peacock Blue
(tested it without the colorants and with)

Without colorants: semigloss clear, washes out the iron and the underglaze
slightly, crazed very slightly where pooled but not anywhere else.

With colorants: not really peacock blue, more a hunter/forest green semi
translucent with iron oxide looking really nice underneath and underglaze
also peeking through.

II. Yikes, guess I didn't save all the glaze names, sorry, color: opaque white
I tested with and without tin oxide, both versions a VERY dry surface, not
really functional, I'd say it needs more flux. Colorants show through on
both, both are white (at least in their unmelted state).

III. Glaze name: V.C. G 5
very glossy, crazed, washed almost all the iron oxide out, underglaze is
nice underneath.

IV. Glaze name: V. C. Karen Weinkauf
nice semi gloss surface, great melt, iron and underglaze nice underneath,
slight craze where pooled

V. Glaze name: Matt Base 5
beautiful semi matt, nice melt, washed out iron slightly, underglaze nice.

VI. Glaze name: Transparent 4
very glossy, crazed, iron oxide and underglaze both still bright but sort
of moved in firing...

VII. Transparent Glossy 3
glossy, crazed, washed out iron oxide, sort of washed out underglaze but
not totally

VIII. no name (sorry)
My absolute favorite of all, semi matt, beautiful surface, iron and
underglaze relatively stable underneath.

IX. Basic
gloss, crazed, iron and underglaze VERY stable underneath, if this glaze
wasn't crazed I'd like it the best for leaving the underneath decoration
the most like intended.

X. Gloss Clear (not sure where I got this, send for recipe)
glossy, not crazed, left iron and underglaze fairly stable

XI. Satin White (tested without tin oxide)
semi opaque white (even without tin!) semi gloss, no craze, colorants look
nice underneath although partially covered by magnesium on surface.

More test results to come, pink and purple (not!) tests at same temp/atmosphere.

Michelle Lowe, potter in the Phoenix desert \|/ | -O- | | /|\ | | |
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