David P George on wed 22 mar 06
This ^6 variant attributed to Gloria Singer appeared in a 2005 issue of
Clay Times (sorry can't remember the month).
^6 Variant of AA Green (Gloria Singer)
Cornwall Stone 45
Whiting 34
EPK 16
Frit 3124 5
100
Add:
Zinc Oxide 5
Copper Carbonate 4
Tin Oxide 4
I have not tested this glaze yet and cannot comment on its durability,
leaching, etc. Would be interested to learn if anyone on the list has
tried this or the previously posted variant with success. I will be
firing it in ^6 reduction +/- zinc. I do not currently have a glaze calc
program but may try the test copy I picked up in the Clayart room.
In the same issue was an article by Richard Burkett who also recommended
using additions of Frit 3124 to lower the firing temperature of ^10
glazes, suggesting that 5-10% would lower the firing temperature by 1-2
cones. Perhaps the glaze gurus will comment on this? Is Frit 3124 the
best choice and would trials of 5, 10, 15, 20% be reasonable to lower the
temp to ^6?
Dave George,
A regular lurker in Puyallup, WA
Judy Shreve on wed 22 mar 06
Rikki
To order Val Cushings handbook write to (Elsie -- his wife) at RR1 Box 236/1497 Water Wells Road/Alfred Station, NY 14803. The book is $24 which includes shipping. It's a great book!
The AA Copper I posted yesterday is the ^10R version.
The ^6 oxidation version:
Cornwall Stone 23.0
Whiting 35.0
EPK 23.0
Frit 3134 10.0
Zinc Ox 5.0
100.0
Copper Carb 4.0
Tin Ox 4.0
Again, when I asked Ron Roy about this glaze he cautioned that this glaze wouldn't be stable and that it has too much copper.
Judy Shreve
Mountain House Studios
Alpharetta GA
"Would you mind just posting to the list? I was about to call Bacia about
how to buy Val Cushing's glaze book, because I would like the cone ten
version.
Thanks,
Best, Rikki"
Noel Jensen on thu 23 mar 06
Dave,
I experimented with three of the cone 10 glazes listed on page 56 of
that issue (September/October 2005). I don't have the issue with me, but
I think the glazes were Shamo Yellow, Oatmeal, and Yellow Orange Matte.
Anyway, I added 5 percent each of 3110, 3124, 3134, 3195, and borax to
small cup-sized batches. With any of these additions, the Oatmeal and
Yellow Orange Matte came out nice satin mattes at cone 6. The Shamo
Yellow was still quite dry.
Noel
noeljensen@comcast.net
David P George wrote:
>This ^6 variant attributed to Gloria Singer appeared in a 2005 issue of
>Clay Times (sorry can't remember the month).
>
>^6 Variant of AA Green (Gloria Singer)
>
>Cornwall Stone 45
>Whiting 34
>EPK 16
>Frit 3124 5
>
> 100
>
>Add:
>
>Zinc Oxide 5
>Copper Carbonate 4
>Tin Oxide 4
>
>I have not tested this glaze yet and cannot comment on its durability,
>leaching, etc. Would be interested to learn if anyone on the list has
>tried this or the previously posted variant with success. I will be
>firing it in ^6 reduction +/- zinc. I do not currently have a glaze calc
>program but may try the test copy I picked up in the Clayart room.
>
>In the same issue was an article by Richard Burkett who also recommended
>using additions of Frit 3124 to lower the firing temperature of ^10
>glazes, suggesting that 5-10% would lower the firing temperature by 1-2
>cones. Perhaps the glaze gurus will comment on this? Is Frit 3124 the
>best choice and would trials of 5, 10, 15, 20% be reasonable to lower the
>temp to ^6?
>
>Dave George,
>A regular lurker in Puyallup, WA
>
>______________________________________________________________________________
>Send postings to clayart@lsv.ceramics.org
>
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>
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>
>
>
Marcia Selsor on thu 23 mar 06
Dear David,
Years ago the rule of thumb (before computer programs were so readily
available)
the procedure for adjusting a ^10 glaze to ^6 was the change the
feldspar to Neph. syn. and add 10%
colemanite...then it became gerstley Borate...which is often now
substituted by Ferro Frit 3124.
You will still need to "tweak" your glaze ..maybe, but that is the
start of adjusting it.
To adjust the surface texture, you alter tha ratio between silica and
alumina.
The adjustment in the melting temperature is the ratio between the
fluxes column and the silica.
At least that's how I was taught.
Marcia Selsor
http://marciaselsor.com
On Mar 22, 2006, at 9:21 PM, David P George wrote:
> This ^6 variant attributed to Gloria Singer appeared in a 2005
> issue of
> Clay Times (sorry can't remember the month).
>
> ^6 Variant of AA Green (Gloria Singer)
>
> Cornwall Stone 45
> Whiting 34
> EPK 16
> Frit 3124 5
>
> 100
>
> Add:
>
> Zinc Oxide 5
> Copper Carbonate 4
> Tin Oxide 4
>
> I have not tested this glaze yet and cannot comment on its durability,
> leaching, etc. Would be interested to learn if anyone on the list has
> tried this or the previously posted variant with success. I will be
> firing it in ^6 reduction +/- zinc. I do not currently have a
> glaze calc
> program but may try the test copy I picked up in the Clayart room.
>
> In the same issue was an article by Richard Burkett who also
> recommended
> using additions of Frit 3124 to lower the firing temperature of ^10
> glazes, suggesting that 5-10% would lower the firing temperature by
> 1-2
> cones. Perhaps the glaze gurus will comment on this? Is Frit 3124
> the
> best choice and would trials of 5, 10, 15, 20% be reasonable to
> lower the
> temp to ^6?
John Hesselberth on thu 10 jan 08
On Mar 22, 2006, at 11:21 PM, David P George wrote:
> This ^6 variant attributed to Gloria Singer appeared in a 2005 =20
> issue of
> Clay Times (sorry can't remember the month).
>
> ^6 Variant of AA Green (Gloria Singer)
>
> Cornwall Stone 45
> Whiting 34
> EPK 16
> Frit 3124 5
> 100
> Add:
> Zinc Oxide 5
> Copper Carbonate 4
> Tin Oxide 4
>
> I have not tested this glaze yet and cannot comment on its durability,
> leaching, etc. Would be interested to learn if anyone on the list has
> tried this or the previously posted variant with success.
Hi Dave,
Below is the unity formula and the comments I wrote when I evaluated =20
this glaze for Clay Times. Bottom Line: It is very low on silica and =20
that combined with a high level of copper makes it totally unsuitable =20=
for use on functional work in my opinion. It is not a glaze I could =20
recommend for anything but sculptural or decorative work.
Regards,
John
> Recipe Name: Gloria's AA Green
>
> Unity Oxide
> .068 Na2O
> .04 K2O
> .005 MgO
> .759 CaO
> .128 ZnO
> 1.000 Total
>
> .283 Al2O3
> .021 B2O3
> .003 Fe2O3
>
> 1.515 SiO2
> .002 TiO2
> .004 P2O5
>
> 5.4 Ratio
> 8.3 Exp
>
> Comments: "X" This glaze is very low on silica. With a =20
> relatively high level of copper it is almost certain to have poor =20
> durability and leach significant quantities of copper on exposure =20
> to acidic foods. I recommend it be used only on decorative or =20
> sculptural work.
> -----------------------------------
> Calculations by GlazeMaster=99
> www.masteringglazes.com
> ------------------------------------
>
John Hesselberth
www.frogpondpottery.com
"Man is a tool-using animal....without tools he is nothing, with =20
tools he is all" .... Thomas Carlyle
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