Alex Solla on thu 20 jul 06
Howdy Ivor-
Looking more closely at these two maganese minerals, I think I can see why making a pink with MnO2 isnt terribly feasible... alumina is going to be present. Without alumina, you would have essentially a manganese silicate of sorts... that is most likely what accounts for the pink.... not sure WHY the pink forms... because like you, most of the time, I have seen Mn head in the purple, or honey direction. My guess would be that the pink is nearly a spinnel stain, potentially contaminated ever so slightly by iron. In essence, the Mn might act more as a flux, less as a colorant, and the iron is there in tiny amts. Not really sure how the Mn is going into solution though but my guess is that the geothermal/hydrothermal process is affecting the solubility of the Mn. But then again, that is just a guess on my part.
-Alex
Some notes from : webmineral.com
http://www.webmineral.com/data/Rhodonite.shtml
Calcium 1.55 % Ca 2.17 % CaO Magnesium 0.38 % Mg 0.62 % MgO Manganese 38.29 % Mn 49.44 % MnO Iron 0.86 % Fe 1.11 % FeO Silicon 21.75 % Si 46.53 % SiO2
Oxygen 37.17 % O
______ ______ 100.00 % 99.88 % = TOTAL OXIDE
cheers,
Alex Solla
Cold Springs Studio Pottery
4088 Cold Springs Road
Trumansburg, NY 14886
607-387-4042 voice/fax
www.coldspringsstudio.com
Ivor and Olive Lewis wrote:
Dear Hank Murrow ,
I was taken by this quotation <<... Maija Grotell used to say(to my teacher), "You can get any color that an oxide is in nature to make that color at any temperature with that oxide in a glaze."...>>
So, have you ever encountered a bright vivid Pink when using one of the manganese chemicals in a glaze. I ask because I have worked with two Manganese minerals, Rhodonite and Rhodocrosite. I have achieved a violet hue but more frequently the colour in stoneware glazes is yellow ochre to a deep rich golden honey. Recently I have attained what might be termed a rich dark weak Red Umber. But so far, no Pink.
As for Marianne's question. I'm still thinking about what she asks.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
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Ivy Glasgow on fri 21 jul 06
And yet one of these solipsistic glaze books happily asserts that a
satisfactory pink will be achieved with "1-5% manganese in Alkaline
glazes opacified with tin or titanium. Also in high alumina glazes."
No test tile photo alongside that suggestion, mind you.
Just goes to show that the published word has no superiority
over the combined wisdom of the clayarters...
-Ivy G.
--- In clayart@yahoogroups.com, Ivor and Olive Lewis
wrote:
>
> Dear Hank Murrow,
>
> Sorry to disappoint you but I have never recorded Pink from a
manganese glaze. Only once have I had a Violet and that came out of a
Seger Cone 8 electric kiln at Sunderland College of Art. At that time
I was not making glazes, we used the ready mades and just added
colouring oxides.
>
> But if Maija Grotell was correct in her assertion then Pink must be
possible since there are pink Manganese Minerals. Yes, there is a Pink
Cobalt mineral.
>
> Best regards,
>
> Ivor Lewis.
> Redhill,
> South Australia.
>
Hank Murrow on fri 21 jul 06
On Jul 21, 2006, at 9:45 AM, Ivy Glasgow wrote:
> the published word has no superiority
> over the combined wisdom of the clayarters...
Say Ivy;
Here is a reference from David Stannard concerning color in glaze/glass:
> W.A.Weyl wrote a book, collected 1930s series of articles from Ceram.
> Soc.,
> called "Colored Glasses" (Dawsons of Pall Mall, 1959) which I found
> *very*
> useful for the static "network former/modifier theory" treatment. Good
> for
> imagining competing color tendencies. Later he switched to Dynamic
> modelling-- more satisfying for professionals, & for me in principle,
> but
> too hard to follow & make simple-minded shop use of it!)
Don't know if the book is available, but it might help your
imaginings.....
Cheers, Hank
www.murrow.biz/hank
Ivor and Olive Lewis on sat 22 jul 06
Dear Hank Murrow,=20
Yes the text by W.A.Weyl is a good introduction to the Science of =
Coloured Glass. I think he compiled it originally for the Glass Research =
Division at the University of Sheffield.
Another good early source for ceramic knowledge is Singer and Singer, =
"Industrial Ceramics".
For the studio potter and ceramic artist Cooper and Royle is a =
reasonably comprehensive text covering major issues.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
Ivor and Olive Lewis on sat 22 jul 06
Dear Ivy Glasgow,
Since I am the one who has posed this challenge perhaps you could tell =
me which of the <<... solipsistic glaze books happily asserts that a =
satisfactory pink will be achieved with "1-5% manganese in Alkaline =
glazes opacified with tin or titanium. Also in high alumina =
glazes."...>>
And why "Solipsistic" ? Are you suggesting that Glaze Technology be =
regarded as a branch of "Metaphysics"
Best regards,
Ivor Lewis.
Redhill,
South Australia.
Ivy Glasgow on sat 22 jul 06
On Sat, 22 Jul 2006 15:58:27 +0930, Ivor and Olive Lewis
wrote:
>Dear Ivy Glasgow,
>
>Since I am the one who has posed this challenge perhaps you could tell me
which of the <<... solipsistic glaze books happily asserts that a
satisfactory pink will be achieved with "1-5% manganese in Alkaline glazes
opacified with tin or titanium. Also in high alumina glazes."...>>
>
>And why "Solipsistic" ? Are you suggesting that Glaze Technology be
regarded as a branch of "Metaphysics"
>
Ivor,
This is as in Robin Hopper's "The Ceramic Spectrum". And what I quoted is
*all* of the information provided on manganese pink.
Not sure about the meta-physics. Perhaps I am using the word in a different
way than it's intended. Just trying to say that in some of the books the
information is put forth as if it is in a vacuum, without regard to how
someone might actually put it to use, and without any effort made to prove
that what they say is true.
Thinking more about the glaze for all occasions. There is a possible example
in The Ceramic Spectrum book. It starts with a base formula of 83 parts
comprising the ever-present alumina, silica, and calcium. "To make the glaze
up to 100 parts, add any flux or mixture of fluxes to a total of 17,
depending on the desired color and texture quality." For example, 17 parts
frit, or split it into 10 parts barium and 7 parts frit.
-Ivy G.
John Britt on sat 22 jul 06
Ivy G.
I haven't been following this thread as I have been away at a workshop,
but you might try this:
CHUNG'S SATIN BASE cone 10 Reduction (It is nice in oxidation too)
F-4 Feldspar 35.70
Nepheline Syenite 21.40
Whiting 14.30
EPK Kaolin 14.40
Barium Carbonate 7.10
Zinc Oxide 7.10
For Pink:
add: 0.5 Manganese Dioxide
This is from a color test that Lynne Berman, of the famed Long Beach
Island Foundation of Arts and Sciences, did and was kind enough to share
it with me. It was "pink".
Now you would have to define "pink". It is definitely not cotton candy
pink, but it is a nice soft pink, kind of on the lavender side. Sorry no
photos.
Also, sorry to all those who like a more =93standardized=94 or exhaustive wa=
y
of listing recipes=85=85=85=85=85.. But since I only have a little time, thi=
s is the
best I can do.
Let us know how it goes.
Hope it helps,
John Britt
www.johnbrittpottery.com
Ivor and Olive Lewis on sun 23 jul 06
Dear John Britt,=20
I set this thread in motion after a quotation was given that any colour =
that is found in natural minerals can be imitated in a glaze.
I selected Manganese. Two minerals, Rhodonite and Rhodochrosite, which =
are both true pinks without the lavender cast. I cut a cabochon from =
Rhodonite and mounted it in Copper. This stone has a Scarlet hue.
Thank you for the recipe.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
=20
Ivor and Olive Lewis on sun 23 jul 06
Dear Ivy Glasgow,=20
I was wondering what you meant to infer by using the term "Solipsistic". =
Several years ago when Robin (a gentleman I have met) first published =
his "Ceramic Spectrum" I had a look at a copy and thought of better ways =
of spending fifty dollars.
I do not think authors have control over the way their texts will be =
used.
In the example you have selected, where 83% of a recipe is given I think =
Robin is hypothesising to illustrate the concept that the reader could =
select a further proportion of materials that might assist the fusion of =
the glaze. This is a function often referred to as "Tweaking", adjusting =
a given recipe to make it work on the clay that you are using. Perhaps =
this approach has more in common with Cookery than Science.
If you wish to pursue Glazing in a scientific or technological way then =
you have to return to First Principles and explore possibilities in a =
systematic way. Because there are so many mistaken or misused concepts =
to be found in current popular glaze literature I prefer to thing to the =
task as one of Design rather than Science.
In other words, a ceramic artist has to write a Design Brief for a =
Glaze, a specification for what has to be made, then use such knowledge =
and resources as are available to achieve that task. Again Mel Jacobson =
set us a fine example in his cooperative work on the Ancient Iron =
Glazes.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
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