John Britt on mon 12 jul 04
Sea Salt added to Glazes or Clay
Mark,
Penn State Shino -Cone 10
14.60 -Nepheline Syenite
34.00 -F-4 Feldspar
29.00 -Spodumene
9.70 -EPK Kaolin
4.90 -Kentucky Old Mine #4
7.80 -Soda Ash
This is a high feldspar shino. (approximately 77% feldspar). It acts
different than a high clay shino.
The iron in the slip or wash can rise through the glaze coat and give
lusterous surfaces, especially in high reduction.
Often potters add salt to shino glazes to =93spice=94 things up. I have foun=
d
that the salt flocculates the glaze a bit and can result in crawling.
Hope it helps,
John Britt
www.johnbrittpottery.com
kterpstra on tue 13 jul 04
Sea Salt added to Glazes or Clay
Hi Mark,
The Aussie shinos that Lee Love mentioned have been around for awhile in
the states too. Forgive me...i'm having a "senior moment" and can't
remember which way it is but on a light clay body if you vary the amount
of neph sy vs. epk in my experience, it will very the color of flashing
from reds to yellows in a wood kiln. It's a simple way to start
experimenting with flashing slips. Clay bodies have a lot to do with
the color so if you experiment with the slips, keep the clay body the
same. Then do the opposite...vary the clay bodies with the same slip.
This will give you years of testing!
One of my favorite slips for awhile has been Shaner Shino Slip. It's
most likely been tweaked over the years and don't get it confused with
Shaner Shino glaze. On porcelain this flashes more salmon to peach and
if I'm lucky some yellow here and there, and then if I'm really lucky a
little ash here and there in just the right spots. You can see some
examples on my website. http://www.uwlax.edu/faculty/terpstra/ click on
woodfired porcelain.
The recipe is:
Shaner Shino Slip (for wood)
Soda Ash 3 60
Spodumene 13 260
Kona F-4 8 160
Neph Sy 36 720
EPK 28 560
Ball Clay 12 240
100 grms 2000 gms.
spray on greenware. Porcelain or stoneware
have fun!
Karen Terpstra
La Crosse, WI
http://www.uwlax.edu/faculty/terpstra/
http://www.terpstra-lou.com
-----Original Message-----
From: Mark Potter [mailto:mark.potter@SEXTANTSEARCH.COM]
Sent: Monday, July 12, 2004 11:07 AM
Subject: Shino Questions from a Woodfiring - Brown Shino? Yellow Shino??
- Sea Salt added to Glazes or Clay
Dear Folks at ClayArt:
(snip)
HUGE RANGE OF COLORS FROM ONE GLAZE??
I'm new at wood firing but have done a lot of shino with gas. I cannot
account for the enormous variety of colors coming from this one shino
glaze. Greys to reds to yellows! So many factors to consider, a huge
range of temperatures within the kiln (probably 3-4 cones) the fact that
some parts of the kiln went to very high temperatures (Cone 12 anyway),
the cyclical way the kiln was fired - reduction to oxidation and back
(with each load of firewood) - the fact I elected to use a shino glaze I
was unfamiliar with .
. . Prior years the kiln was salted, but not this year . .
YELLOW ????
I also glazed a small white bottle with the same shino - and get this -
got a lovely yellow result. Yes yellow. Not pottery barn yellow, but a
rich yellow streaked with red and brown. I'm perplexed about what
happened. Ideas? I'll try and post pictures. Can Shino produce a yellow?
SEA SALT / SALT IN GLAZE RECIPES
My next question is about adding salt or sea salt to glaze recipes, or
even clay. What does this do, and what kind of changes can one expect to
see to glazes if you add salt to glaze or clay materials instead of
salting the kiln.
Lee Love on tue 13 jul 04
Sea Salt added to Glazes or Clay
Mark Potter wrote:
>PENN STATE SHINO?? HEARD OF IT??
>
>
>
Penn. State Shino
Neph. Sye. 14.6
Soda Ash 7.8
EPK 9.7
OM #4 4.9
Soda Spar 34.0
Spodumene 29.0
>HUGE RANGE OF COLORS FROM ONE GLAZE??
>
>
Mark, many of us fire in wood because of the range of colors
possible. You don't have to get only "Brown" from a wookiln.
>SEA SALT / SALT IN GLAZE RECIPES
>
>
Jeff Oestrich gave me this recipe years ago (It was at Jeff's that I
drank from a lovely Arbuckle majolica tea cup for the first time), and
Tony listed it recently at the Wookiln list (to subscribe send email
to: WoodKiln-subscribe@yahoogroups.com) :
Aussie Shino
70 nep sy
30 kaolin
3% table salt
Aussie Shino (Shinier Version)
80 nep sy
20 kaolin
3% table salt
If you go here, you can see the recipe as it looks without salt or soda.
(some of Craig Edward's new work) :
http://img2.photobucket.com/albums/v11/credwards/Shino%20Cup/?sort=descending
--
Lee in Mashiko, Japan http://mashiko.org
http://journals.fotki.com/togeika/Mashiko/ Commentary On Pottery
Paul Herman on thu 15 jul 04
Sea Salt added to Glazes or Clay
Mark,
I'll make a few comments, below:
Paul Herman
Great Basin Pottery
Doyle, California US
http://www.greatbasinpottery.com/
----------
>From: Mark Potter
> Anyway I have a bunch of questions for you Shino gurus:
>
> I was recently out at Rodney Mott's legendary woodfiring of his "Big
> Mama" kiln, in Penryn CA - (Woodstoke 2004). I have questions to you
> knowledgeable wood-firers about some of my results.
> VERY UNUSUAL RESULTS
A large kiln like that gives a large range of effects.
>
> I used this Penn State Glaze over a number of cups, some of which were
> coated with an iron rich clay slip. The cups came out a gorgeous red
> brown, almost temoku or shaner's red in tone, not at all 'shino-ish' in
> color. This happened to cups that did not receive much flashing or ash
> deposition.
A little iron goes a long way with shino and extended firing. It doesn't
take much. If you use a "brown" stoneware clay in there it will come out
VERY dark.
This woodfiring produced some very heavy reduction (there
> was even some carbon trapping in the firing) and parts of the kiln were
> overfired. Loss rates were heavy. But some of the results were
> breathtaking.
Too bad about the heavy losses. It takes a lot of meticulous
attentention, particularly in the loading, to get those losses down.
Last firing here took five days to load. I'm wondering how the loading
looked to you. Was it done all in one afternoon?
>
> HUGE RANGE OF COLORS FROM ONE GLAZE??
>
> I'm new at wood firing but have done a lot of shino with gas. I cannot
> account for the enormous variety of colors coming from this one shino
> glaze. Greys to reds to yellows! So many factors to consider, a huge
> range of temperatures within the kiln (probably 3-4 cones) the fact that
> some parts of the kiln went to very high temperatures (Cone 12 anyway),
> the cyclical way the kiln was fired - reduction to oxidation and back
> (with each load of firewood) - the fact I elected to use a shino glaze I
> was unfamiliar with .
> . . Prior years the kiln was salted, but not this year . .
If it was salted last year, you got a little salt on top of your shino.
The huge range of temperature, etc., showed up on your pots.
>
> YELLOW ????
>
> I also glazed a small white bottle with the same shino - and get this -
> got a lovely yellow result. Yes yellow. Not pottery barn yellow, but a
> rich yellow streaked with red and brown. I'm perplexed about what
> happened. Ideas? I'll try and post pictures. Can Shino produce a yellow?
In my experience, salt kilns encourage yellow sometimes.
>
>
> SEA SALT / SALT IN GLAZE RECIPES
Never have tried salt in the glaze.
It takes a few firings to start to see how the kiln works, the first one
is pretty mysterious.
best,
Paul Herman
Great Basin Pottery
Doyle, California US
http://www.greatbasinpottery.com/
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