Earl Brunner on tue 21 jul 98
In my glaze note book I have the following information. I think it was taken
from an article in Ceramics Monthly (I think) some time in the 70's. Other
than that I don't have a clue anymore on the source. The chart is entitled,
"Matting agents and their affects on colorants. It might help.
Alkaline Glazes - containing considerable barium, calcium, zinc, magnesium
Whiting 4% red Fe -Yellowish, 3% copper carb -Turquoise, 3% manganese
dioxide - violet brown, 1% cobalt carb- light blue, 1% chrome oxide - light
green
Barium iron - ochre, copper - blue greens, manganese - dark brown, cobalt -
blue, chrome - yellow
Zinc iron - orange brown, copper - blue greens, manganese - violet brown,
cobalt - luminous blue, chrome - ?
titanium iron - yellowed, copper - turquoise, manganese - violet brown,
cobalt - dark blue,
dioxide chrome - green brown
talc iron - pale yellow, copper - turquoise, manganese - milky, cobalt -
light blue, chrome - light green
kaolin iron - red browns, copper - bottle green, manganese - rust brown,
cobalt - luminous blue, chrome - moss green
Acidic Glazes - high silica, tin, titanium, zircon
whiting 45 red Iron - dark brown, 3% copper carb. - green, 3% manganese
dioxide - dark
brown, 1% cobalt - violet blues, 1% chrome oxide - gray green
barium iron - yellow brown, copper - green, manganese - dark brown, cobalt -
blues
chrome - yellow greens
zinc iron - yellow brown, copper - light green, manganese - dark brown,
cobalt - dark blue, chrome - ?
titanium iron- light brown, copper - blue green, manganese - chocolate brown,
cobalt -
dioxide gray green
talc iron - dark brown, copper - moss green, manganese - brown, cobalt -
violet
blue, chrome - green brown
kaolin iron - modulated, copper - light green, manganese - dark, cobalt -
pigeon
blue, chrome - light green
Back in the days before glaze software, (before PC's actually) I used this
chart as a reference as to A) whether a glaze was acidic or alkaline, and B)
to select the ingredients I needed to shift certain colorants certain
directions, say for example copper blue instead of green. It was a good
"general" indicator.
Earl Brunner
Las Vegas
brunnerec@aol.com
Maggie Woodhead on tue 21 jul 98
Using 'Insight' I have compiled four glaze recipes which
test out well and wish to use one of them as the base for coloured
decorative glazes i.e. rutile blues with and without cobalt, a good
chun for over my tenmoku and if possible at a later date a copper
red, using oxides. My difficulty is that I need to find more
information regarding the materials conducive to developing them.
So far the glazes while being suitable for all normal uses are
giving me poor results. I have read up a few notes such as higher
sodium and silica but cannot find much else. Do I need to use other
limit formulae for this purpose.
Thanks to all in anticipation.
----Best Wishes Maggie----
maggie@clear.net.nz
Ron Roy on wed 22 jul 98
Hi Maggie,
Time to get The Potters Dictionary of Materials and Tecckniques by Frank
and Janet Hamer - pricy but illuminating.
>Using 'Insight' I have compiled four glaze recipes which
>test out well and wish to use one of them as the base for coloured
>decorative glazes i.e. rutile blues with and without cobalt, a good
>chun for over my tenmoku and if possible at a later date a copper
>red, using oxides. My difficulty is that I need to find more
>information regarding the materials conducive to developing them.
>So far the glazes while being suitable for all normal uses are
>giving me poor results. I have read up a few notes such as higher
>sodium and silica but cannot find much else. Do I need to use other
>limit formulae for this purpose.
Ron Roy
93 Pegasus Trail
Scarborough, Ontario
Canada M1G 3N8
Tel: 416-439-2621
Fax: 416-438-7849
Web page: http://digitalfire.com/education/people/ronroy.htm
Richard Gralnik on thu 23 jul 98
Everyone,
Earl helped me clean up the format of his post on the coloring effects
of different minerals in alkaline and acidic glazes so I could read it
more easily. He also corrected a couple of things for me. Here is
the result of that update. It helped me read the list more easily.
I hope it helps others who wanted to benefit from the information.
Richard
At 10:21 PM 7/21/98 EDT, you wrote:
>In my glaze note book I have the following information. I think it was taken
>from an article in Ceramics Monthly (I think) some time in the 70's. Other
>than that I don't have a clue anymore on the source. The chart is entitled,
>"Matting agents and their affects on colorants. It might help.
>
>Alkaline Glazes - containing considerable barium, calcium, zinc, magnesium
>Whiting 4% red Fe -Yellowish,
> 3% copper carb -Turquoise,
> 3% manganese dioxide - violet brown
> 1% cobalt carb - light blue
> 1% chrome oxide - light green
>Barium iron - ochre
> copper - blue greens
> manganese - dark brown,
> cobalt - blue
> chrome - yellow
>Zinc iron - orange brown
> copper - blue greens
> manganese - violet brown,
> cobalt - luminous blue
> chrome - ?
>titanium dioxide iron - yellowed
> copper - turquoise
> manganese - violet brown,
> cobalt - dark blue,
> chrome - green brown
>talc iron - pale yellow
> copper - turquoise
> manganese - milky,
> cobalt - light blue
> chrome - light green
>kaolin iron - red browns
> copper - bottle green
> manganese - rust brown
> cobalt - luminous blue
> chrome - moss green
>
>Acidic Glazes - high silica, tin, titanium, zircon
>whiting 4% red Iron - dark brown
> 3% copper carb. - green,
> 3% manganese dioxide - dark brown
> 1% cobalt - violet blues
> 1% chrome oxide - gray green
>barium iron - yellow brown
> copper - green
> manganese - dark brown
> cobalt - blues
> chrome - yellow greens
>zinc iron - yellow brown
> copper - light green
> manganese - dark brown
> cobalt - dark blue
> chrome - ?
>titanium dioxide iron- light brown
> copper - blue green
> manganese - chocolate brown
> cobalt - blue green
>talc iron - dark brown
> copper - moss green
> manganese - brown
> cobalt - violet blue
> chrome - grey green
>kaolin iron - modulated
> copper - light green
> manganese - dark
> cobalt - pigeon blue
> chrome - light green
>
>Back in the days before glaze software, (before PC's actually) I used this
>chart as a reference as to A) whether a glaze was acidic or alkaline, and B)
>to select the ingredients I needed to shift certain colorants certain
>directions, say for example copper blue instead of green. It was a good
>"general" indicator.
>
>Earl Brunner
>Las Vegas
>brunnerec@aol.com
>
>
Christine Sawyer on tue 27 jul 99
What is a save level of the total oxides in a glaze=21 Is there a rule of =
thumb
or is it depended on each type of oxide being used.
james pendergrass on sun 10 oct 99
I have 2000 lbs. of Glaze and underglaze Color pigments for sale,for
one dollar a pound. If interested call 615-650-8988 James Pendergrass
Bill Edwards on wed 10 dec 03
I agree with John H. that they are an occasional
glitch out there in the oxides department. Cobalt carb
or oxide as well as others sometimes come in weaker
versions than we intended on getting. Another good
reason to ask for pertinent product sheet info which
would include the strength of the product and impurity
if applicable. Competition to get a popular product in
the hands of users seems pretty good in the marketing
arena but just make sure you seek the proper
information before spending money on products that
don't stand up. Most good suppliers are particular
about what they stock so if you find a good source I
would stick to it even if they do seem higher than the
guy down the road. Chances are good they paid more in
order to get the best!
Alisa - Its all good. For those just now getting their
hands wet they see the shifts and changes it takes and
learn about tweaking and the if's and how's. Your
picture site was a great contribution and while I have
built a site and have it up for some of that kind of
information, I have yet to add one thing to it. Time
is not in my favor right now at all! What some fail to
see especially if they are starting out is this: Many
products change. Frits are mostly consistent and some
of the feldspars. But clays and additives and
colorants can be a hassle to keep up with. Then each
kiln will fire a little differnt or each pottery will
fire a little different which will effect the
out-come. Its really good to see all this because over
the years there has been improvement in glaze theory.
There's yet to be a concise answer to every question
but many people are producing much better and safer
wares with great aesthetics at the same time. Theres
still some doozies that won't fit the parameters known
for durability and minor changes will effect them but
most also realize they are sensible artists that know
exactly when and where to use them!
Below is a good glaze that I like to use. This one
will be interesting to see once its been re-calculated
several times. I hope some pictures will come from it
as its posted first.
I do have the molecular formulation but will wait and
see what others calculate it as. This is a good
exercise on the differences of what has been imputted
into our systems but the outcome should be similar if
the product used, is as stated.
EDWARDS MATTE SLIP GLAZE ^6 OX. Cone 6
-------------------------------------------------------
Formula Weight% Recipe
-------------------------------------------------------
OM-4 Ball Clay 40.00
Ferro 3124 30.00
Dolomite 20.00
EPK Kaolin 10.00
Peronally I only use small amounts of coloring oxides
but heres one I love to use. 4% Rutile and 4% Spanish
Red Iron Oxide. Using regular high grade red iron
works well also and is very pretty. This glaze can be
used in several ways. Thinned for dipping or thick as
a slip. Testing it on your clay choice is up to you.
It works for me both ways on the clays I use and is a
nice decorative finish. Sometimes I will slip some of
it and then use the thinned version for dipping using
various oxides to achieve differnt features such as an
over-glaze effect. Meaning the slip might contain a
heavy load of iron with the thinner mix being the
oxide content shown above for dipping. Lets see some
pictures from all you glazers out there using your own
techniques. It will show incising and lines well if
dipped making it usefull there. Another hint - Black
10% RIO 2.5% Cobalt Carb.
Bill Edwards
=====
http://www.geocities.com/tallapoosarivergallery/index.html (Coming soon)
http://www.tallapoosariverpottery.com/
Bill Edwards
PO Box 367
Camp Hill, Alabama. 36850
__________________________________
Do you Yahoo!?
New Yahoo! Photos - easier uploading and sharing.
http://photos.yahoo.com/
Ron Roy on sat 13 dec 03
Hi Bill,
Here is my make over - just so everyone understands about this glaze - it
is probably not well melted enough to be stable and is certainly short of
silica - like many high alumina mattes are. John is pretty well convinced
that high alumina mattes are almost impossible to make durable.
OM 4 - 59.0
F3134 - 17.0
Dolomite - 21.0
EPK - 3
Total - 100.0
Ratio (SiO2 to Al3O2) 4.04 (the original is 4.11)
Calculated expansion is about the same - but unreliable because it is a
matte glaze. Be warned calculated expansion is low - this means the real
expansion could be higher or lower - if it's lower this could be a post
buster - test it as a liner - glaze only the inside of a thinly thrown pot
made of all the clays you use - keep the glaze a little on the thick side -
the bigger the pot the more any mis fit will show up. After firing - freeze
over night - pour boiling water in while the test piece still frozen - in
the sink in case it cracks. If functional ware survives this kind of test
you don't have to worry about your pots cracking when hot water is poured
into them.
RR
>Below is a good glaze that I like to use. This one
>will be interesting to see once its been re-calculated
>several times. I hope some pictures will come from it
>as its posted first.
>I do have the molecular formulation but will wait and
>see what others calculate it as. This is a good
>exercise on the differences of what has been imputted
>into our systems but the outcome should be similar if
>the product used, is as stated.
>
>EDWARDS MATTE SLIP GLAZE ^6 OX. Cone 6
>-------------------------------------------------------
> Formula Weight% Recipe
>-------------------------------------------------------
> OM-4 Ball Clay 40.00
> Ferro 3124 30.00
> Dolomite 20.00
> EPK Kaolin 10.00
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Susan McBride on fri 22 oct 04
Please bear with me... I'm a newbie! However, during one of my pottery
classes the instructor mixed together an oxide "formula" that could be
applied to bisque and NOT be fired! Once it dried, it didn't wash off.
Unfortunately, she won't pass along the formula.
Has anyone ever heard of this type of finish?
Thank you.
Snail Scott on sat 23 oct 04
At 11:17 AM 10/22/2004 -0400, you wrote:
>Please bear with me... I'm a newbie! However, during one of my pottery
>classes the instructor mixed together an oxide "formula" that could be
>applied to bisque and NOT be fired! Once it dried, it didn't wash off.
>Unfortunately, she won't pass along the formula.
>
>Has anyone ever heard of this type of finish?
Oxides mixed with a binder and applied cold is
what's generally called 'paint'. ;) Seriously,
that's all that any oxide-colored acrylic (or
oil, or any other) paint is: Pigment + vehicle/
binder = paint.
Lots of materials can serve as a binder for
pigment. Few of them would be appropriate for
food-bearing surfaces, of course, but paint is a
perfectly good finish for indoor sculptural work.
Lacquers and shellacs work, as do clear acrylic
medium, polyurethate wood finish, linseed oil,
egg whites, milk, and more.
Or just buy paint. I like acrylics.
-Snail Scott
Ivor and Olive Lewis on sat 23 oct 04
Dear Susan McBride,
What was she using as a liquid to make this flow onto the clay?
What qualities is your instructor claiming for this sort of finish?
Doesn't sound like "Pottery" to me !
Best regards,Ivor Lewis.
Redhill,
S. Australia.
Snail Scott on mon 25 oct 04
Snail wrote:
>> Or just buy paint. I like acrylics.
At 09:28 AM 10/25/2004 -0500, Kate J. wrote:
>Wahoo, is THAT how you do those gorgeous sculptures, Snail?! COOL.
Sometimes. ;) I see no reason why paint on clay is
in any way inferior to paint on canvas, when the
intended outcome is art. For work that will go
outdoors, though, I prefer fired surfaces. Even
the best paint is no match for the weatherproofness
(and archival qualities) of a fired surface.
For foodware, no better finish than glaze has
ever been developed - easy to clean, hygenic,
pleasant against utensils, attractive and easily
varied for aesthetic purposes, nonabsorbent,
leakproof, versatile, and achievable with only basic
technology. Glaze is great stuff, but non-food
ceramics all have their own set of optimum criteria,
and they don't always coincide.
-Snail Scott
Kate Johnson on mon 25 oct 04
>
> Lots of materials can serve as a binder for
> pigment. Few of them would be appropriate for
> food-bearing surfaces, of course, but paint is a
> perfectly good finish for indoor sculptural work.
> Lacquers and shellacs work, as do clear acrylic
> medium, polyurethate wood finish, linseed oil,
> egg whites, milk, and more.
>
> Or just buy paint. I like acrylics.
Wahoo, is THAT how you do those gorgeous sculptures, Snail?! COOL.
I occasionally use acrylic paint on my greenman sculptures when I think
they'd benefit from what can only be called "antiquing," much as I dislike
that word or connotation. I've tried various other methods, including
mason stains and borax then firing, but I don't always know till I'm done
and it's fired that I WANT this particular piece to have that kind of
accentuation.
My owl mask greenman needs it, as it turns out, and I didn't think it would.
So yep, I'll drag out the nice browny-black acrylic paint, thin it, wash it
into the crevices, wipe off excess and let it dry--whatever it takes to get
the effect with your art is fair game, since this is NOT a food piece.
Best--
Kate
Kate Johnson on tue 26 oct 04
> At 09:28 AM 10/25/2004 -0500, Kate J. wrote:
>>Wahoo, is THAT how you do those gorgeous sculptures, Snail?! COOL.
>
>
> Sometimes. ;) I see no reason why paint on clay is
> in any way inferior to paint on canvas, when the
> intended outcome is art.
Exactly! I was thinking of one of your jester pieces, I think it was...a
very fine, precise checkerboard pattern on part of his clothing that seemed
difficult if not impossible to do with glaze...
For work that will go
> outdoors, though, I prefer fired surfaces. Even
> the best paint is no match for the weatherproofness
> (and archival qualities) of a fired surface.
You really need to have more of your work up where I can drool on it! Chris
Schafale is indeed planning a non-functional gallery in the (near?) future
(not noodging, Chris, REALLY!), that would be a great, handy place!
>
> For foodware, no better finish than glaze has
> ever been developed - easy to clean, hygenic,
> pleasant against utensils, attractive and easily
> varied for aesthetic purposes, nonabsorbent,
> leakproof, versatile, and achievable with only basic
> technology.
OH yeah. Glaze necessary on almost all foodware (though I've always
wondered about those unglazed terra cotta chicken cookers...)
Glaze is great stuff, but non-food
> ceramics all have their own set of optimum criteria,
> and they don't always coincide.
Apples and oranges.
Best--
Kate
Snail Scott on thu 28 oct 04
>> At 09:28 AM 10/25/2004 -0500, Kate J. wrote:
>>>Wahoo, is THAT how you do those gorgeous sculptures, Snail?! COOL.
>>
>> Sometimes. ;) I see no reason why paint on clay is
>> in any way inferior to paint on canvas, when the
>> intended outcome is art.
>
>Exactly! I was thinking of one of your jester pieces, I think it was...a
>very fine, precise checkerboard pattern on part of his clothing that seemed
>difficult if not impossible to do with glaze...
Actually, that piece has not much paint at all.
It's mostly slips and engobes.
I covered the whole piece with a yellow slip
with shading in browner tones (applied to
leather-hard clay) and then fired. After firing,
I painted the checkerboard pattern with wax and
then brushed various engobes across it. The wax
allowed me to get the same shading/contouring
in the red/purplish squares that I got with the
yellow/tan underneath without painfully painting
each square shape with the range of colors - a
much freer-looking effect. (Though possibly not
much faster, considering the time spent applying
wax.) Then, I used underglaze pencils to add
the alchemical symbols and physics equations.
After firing, I touched up a few points with a
slightly iridescent paint - not heavy-handed;
just enough to modify what was there. The
final finish on that piece is a UVLS acrylic
varnish.
The only actual glaze on that piece is on the
'implements' around his neck, which are glazed
in a range of dark colors with varying surfaces
(matte, gloss), which after firing were
overglazed with several shades of metallic
luster (gold, 'silver', 'bronze', copper).
After the luster firing, I scotch-brited them
to remove the luster from the high points.
(These are all separate elements attached to
a chain after firing.)
This is the piece shown in this year's 'Clay
Lovers' Calendar for December. (The color's
a little off, though; a bit too 'zippy'.) It
was my first try at digitizing a slide; I'm
getting better!) ;)
-Snail Scott
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