Joyce Lee on mon 5 jan 98
Thanks to John Baymore's post to Clayart back in September, I've been
experimenting with kaki and tenmoku. I've poured the kaki over the
tenmoku very thickly on flatter surfaces such as low bowls and plates.
(My plates are far from great and are way too thick but they look
better than they are with this combination, thank you John B.) That
works. I uderstand the glaze overpours and that still needs practice.
Fluidity of movement is not happening yet (although I definitely got the
part about using plenty of glaze and not worrying about spills. Oh,
yeah.) An area that probably should seem simple but hangs me up and
which research hasn't cleared up is:
1) What is a feldspathic limestone clear? I'm reading Mimi Obstler's
"Out of the Earth into the Fire" which says a lot about limestone,
whiting, calcium carbonate etc but I'm missing something here. Probably
because the 1234 Clear whizzed right past me. I know it must refer to
percentages, probably 25, 25, 25, 25...but of what? Feldspar?
Limestone? and? and? Ignorance is not bliss.
Thank you, John Baymore and all you other pros, for your continuing
generosity to struggling Clayarters such as I.
Joyce
In the cool Mojave where we may have snow on the Sierras tonight.
Craig Martell on tue 6 jan 98
At 10:39 AM 1/5/98 EST, Joyce Lee wrote:
>----------------------------Original message----------------------------
>1) What is a feldspathic limestone clear? I'm reading Mimi Obstler's
>"Out of the Earth into the Fire" which says a lot about limestone,
>whiting, calcium carbonate etc but I'm missing something here. Probably
>because the 1234 Clear whizzed right past me. I know it must refer to
>percentages, probably 25, 25, 25, 25...but of what? Feldspar?
>Limestone? and? and? Ignorance is not bliss.
Hi Joyce:
The other two ingredients would in all probability be clay and silica. Below
is a calculation and receipe of equal parts of the 4 ingredients and it does
make a balanced glaze. It's high in calcium though and may develop lots of
crystals with a slow cool. We did some .8 and .9 limestone sets with the
Currie method and in many cases got some nice crystalline glazes. This
glaze is .86 lime, and may or may not have crystal development. Almost
forgot, you may get a better melt with a direct substitution of ball clay
for EPK. If you have time, try both.
later, Craig Martell-Oregon
Untitled Recipe 1
CUSTER FELDSPAR 25.00 CaO 0.86*
WHITING 25.00 MgO 0.00*
EPK KAOLIN 25.00 K2O 0.09*
SILICA 25.00 Na2O 0.04*
======== Fe2O3 0.00
100.00 TiO2 0.00
Al2O3 0.46
SiO2 3.07
Cost/kg 0.08
Si:Al 6.67
SiB:Al 6.67
Expan 7.06
Kris Griffith on wed 7 jan 98
The clear celedon I am using right now as a base for colorants falls right =
into
this, without the recipi in front of me, from memory I believe it is: 25
Custer, 25 Kaolin, 25 Silica, 25 Whiting - your basic calcuium celedon. =
Since
lime is a alkalin, I would bet an alkalin celedon could be made with the
substitution of the whiting for the limestone. My only concern would be =
with
bloating. Maybe some of the glaze guroos will have an opinion.
Kris
----------
From: Joyce Lee=5BSMTP:Meunier=40ridgecrest.ca.us=5D
Sent: Monday, January 05, 1998 10:39 AM
To: Multiple recipients of list CLAYART
Subject: Kaki/Tenmoku
----------------------------Original message----------------------------
Thanks to John Baymore's post to Clayart back in September, I've been
experimenting with kaki and tenmoku. I've poured the kaki over the
tenmoku very thickly on flatter surfaces such as low bowls and plates.
(My plates are far from great and are way too thick but they look
better than they are with this combination, thank you John B.) That
works. I uderstand the glaze overpours and that still needs practice.
Fluidity of movement is not happening yet (although I definitely got the
part about using plenty of glaze and not worrying about spills. Oh,
yeah.) An area that probably should seem simple but hangs me up and
which research hasn't cleared up is:
1) What is a feldspathic limestone clear? I'm reading Mimi Obstler's
=22Out of the Earth into the Fire=22 which says a lot about limestone,
whiting, calcium carbonate etc but I'm missing something here. Probably
because the 1234 Clear whizzed right past me. I know it must refer to
percentages, probably 25, 25, 25, 25...but of what? Feldspar?
Limestone? and? and? Ignorance is not bliss.
Thank you, John Baymore and all you other pros, for your continuing
generosity to struggling Clayarters such as I.
Joyce
In the cool Mojave where we may have snow on the Sierras tonight.
GURUSHAKTI on wed 7 jan 98
The 25,25,25,25 glaze is the old cone 9 Leach white glaze.
The 1234 glaze is if I remember, correctly, is:
40 Feldspar
30 Flint
20 Kaolin
10 Whiting
Now that I wrote it out I'm thinking that the kaolin and whiting may be
reversed????Anyone out there remember this one?
Regards,
June
Ron Wright on thu 8 jan 98
The book Ceramic Glazemaking by Richard Behrens, has 16 recipes for what
he calls 4-3-2-1 glazes. The closest match to this one is;
cone 6 stony matt
40 potash feldspar
30 flint
20 whiting
10 kaolin
Ron Wright
Shiresham Pottery
http://www.concentric.net/~wrright
GURUSHAKTI wrote:
>
> ----------------------------Original message----------------------------
> The 25,25,25,25 glaze is the old cone 9 Leach white glaze.
>
> The 1234 glaze is if I remember, correctly, is:
>
> 40 Feldspar
> 30 Flint
> 20 Kaolin
> 10 Whiting
>
> Now that I wrote it out I'm thinking that the kaolin and whiting may be
> reversed????Anyone out there remember this one?
>
> Regards,
> June
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