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purples and cremes

updated tue 10 feb 04

 

bill edwards on mon 9 feb 04


I'm curious as to what might be in this glaze that would leach enough to create a hazard in regards to food. Or is it just a poorly designed glaze?

PURPLES AND CREMES^10
>,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
>
>Cone 10 1305 deg.C. -
>,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
>
>Custer feldspar 50.00
>EPK Kaolin 20.00
>Dolomite 16.00
>Calcium Carbonate 8.00
>Wollastonite 6.00
>Bone Ash 8.00
>Red Iron Oxide 1.00
>Rutile 1.50
>Tin Oxide 5.00

Bill Edwards


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Hendrix, Taylor J on mon 9 feb 04


Bill and all,

I don't see anything nasty in this glaze either. I'm practicing my
pencil and paper calculations so below is my work. I've used typical
mineral constants from Cuff. Custer has some Ca and Na, doesn't it. Oh
well.

0.21 K2O
0.58 CaO
0.21 MgO

0.39 Al2O3
1.77 SiO2
0.06 P2O5

RIO .01
Rutile .04
Tin Ox .08

I'm not sure where to put the phosphorous oxide, but I think it's a
glass former. Should I have included the Fe2O3 in with the fluxes? Oh
my. My head is beginning to hurt.

Does this glaze want a bit more Al2O3 for the cone? I know that I'm
working on some calculations for some cone 6 glazes and I have .4 mols
of Al2O3 in them. Cone 10 should be able to take a bit more, right?

Interesting ingredients. Why do you think there is Calcium Carb AND
Wollastonite? Why not CaCO3 to fill the CaO and silica to make up the
difference or maybe more clay to help boost the alumina? Is it the
intimacy thing you think?

Good practice for me.

Taylor, in Waco

-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of bill
edwards
Sent: Monday, February 09, 2004 10:17 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: PURPLES AND CREMES


I'm curious as to what might be in this glaze that would leach enough to
create a hazard in regards to food. Or is it just a poorly designed
glaze?

PURPLES AND CREMES^10
>,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
>
>Cone 10 1305 deg.C. -
>,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
>
>Custer feldspar 50.00
>EPK Kaolin 20.00
>Dolomite 16.00
>Calcium Carbonate 8.00
>Wollastonite 6.00
>Bone Ash 8.00
>Red Iron Oxide 1.00
>Rutile 1.50
>Tin Oxide 5.00