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crystalline glaze. help need with new project

updated tue 20 mar 01

 

Jim Mason on sun 18 mar 01


Ivor,

I'm really new to this but have a couple of glaze calculation programs, a 34
yr. old BS in chemistry, and an interest in crystalline glazes. So, I'd like
to take a try at helping. I'm going to be pretty covered up with travel till
mid-April though.

Best regards,
Jim Mason,
NC

iandol on sun 18 mar 01


I believe that there is potential to create a new style of crystalline =
glaze which will mature in the range of 1150-1250 deg Celsius.The =
predicted crystallisation temperature is in the range of 1125-1100 deg =
Celsius to ensure a vitreous glaze matrix. Crystal incubation time is =
uncertain at this stage and would need experimental determination. Post =
maturity heat treatment could be quite complex but transformation could =
be achieve by two independent routes. To get an investigation underway =
help may be needed to determine glaze recipes.
Do I have friends with Computer Glaze Programs capable of taking the =
following values of oxide mixtures and converting them into recipes =
containing Soda Felspar, Wollastonite, Talc with adjustments provided by =
pure silica, alumina hydrate and/or kaolin. These are the only materials =
permitted. I am unwilling to use carbonates or oxides. I have already =
obtained some results from Cone 8 which seem to fall within the range =
given but due to crash cooling they are all transparent glazes
The oxide mixtures are Na2O3-Al2O3-6SiO2 in the range of 90% to 70% and =
CaO-MgO-2SiO2 with a range of 10% to 30%.
To give some idea of the potential of these hypothetical glazes I =
predict the crystals will be white but can be doped with iron to get a =
green to black coloration. Other transition elements may extend this =
palette.
If no one can help it will be back to the hand calculator, pencil and =
paper and some mental gymnastics.
Looking forward to some results.
Best Regards,
Ivor Lewis. Redhill, South Australia.

ILENE MAHLER on sun 18 mar 01


why no oxides? I am starting to do cone 10 chrystals 2320 degrees,and I
would not be happy without coppers...Ilene in Conn where 1st firing was
a sucess...

iandol wrote:
>
> I believe that there is potential to create a new style of crystalline glaze which will mature in the range of 1150-1250 deg Celsius.The predicted crystallisation temperature is in the range of 1125-1100 deg Celsius to ensure a vitreous glaze matrix. Crystal incubation time is uncertain at this stage and would need experimental determination. Post maturity heat treatment could be quite complex but transformation could be achieve by two independent routes. To get an investigation underway help may be needed to determine glaze recipes.
> Do I have friends with Computer Glaze Programs capable of taking the following values of oxide mixtures and converting them into recipes containing Soda Felspar, Wollastonite, Talc with adjustments provided by pure silica, alumina hydrate and/or kaolin. These are the only materials permitted. I am unwilling to use carbonates or oxides. I have already obtained some results from Cone 8 which seem to fall within the range given but due to crash cooling they are all transparent glazes
> The oxide mixtures are Na2O3-Al2O3-6SiO2 in the range of 90% to 70% and CaO-MgO-2SiO2 with a range of 10% to 30%.
> To give some idea of the potential of these hypothetical glazes I predict the crystals will be white but can be doped with iron to get a green to black coloration. Other transition elements may extend this palette.
> If no one can help it will be back to the hand calculator, pencil and paper and some mental gymnastics.
> Looking forward to some results.
> Best Regards,
> Ivor Lewis. Redhill, South Australia.
>
> ______________________________________________________________________________
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Lawrence Ewing on mon 19 mar 01


Hi Ivor,

I would be happy to help with this project.

Regards,

Lawrence Ewing

-----Original Message-----
From: Ceramic Arts Discussion List [mailto:CLAYART@LSV.CERAMICS.ORG]On
Behalf Of iandol
Sent: Sunday, March 18, 2001 4:10 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Crystalline Glaze. Help need with New Project


I believe that there is potential to create a new style of crystalline glaze
which will mature in the range of 1150-1250 deg Celsius.The predicted
crystallisation temperature is in the range of 1125-1100 deg Celsius to
ensure a vitreous glaze matrix. Crystal incubation time is uncertain at this
stage and would need experimental determination. Post maturity heat
treatment could be quite complex but transformation could be achieve by two
independent routes. To get an investigation underway help may be needed to
determine glaze recipes.
Do I have friends with Computer Glaze Programs capable of taking the
following values of oxide mixtures and converting them into recipes
containing Soda Felspar, Wollastonite, Talc with adjustments provided by
pure silica, alumina hydrate and/or kaolin. These are the only materials
permitted. I am unwilling to use carbonates or oxides. I have already
obtained some results from Cone 8 which seem to fall within the range given
but due to crash cooling they are all transparent glazes
The oxide mixtures are Na2O3-Al2O3-6SiO2 in the range of 90% to 70% and
CaO-MgO-2SiO2 with a range of 10% to 30%.
To give some idea of the potential of these hypothetical glazes I predict
the crystals will be white but can be doped with iron to get a green to
black coloration. Other transition elements may extend this palette.
If no one can help it will be back to the hand calculator, pencil and paper
and some mental gymnastics.
Looking forward to some results.
Best Regards,
Ivor Lewis. Redhill, South Australia.

____________________________________________________________________________
__
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You may look at the archives for the list or change your subscription
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Moderator of the list is Mel Jacobson who may be reached at
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