Paul Herman on mon 3 may 04
Hi Tony,
All the shinos I've tested and the recipes I've seen are mostly feldspar
and clay. Never any calcium added. As John Britt noted, calcium really
affects the way the iron behaves, making green glass (celadon).
The ones I've used are high in alumina, from clay. I think the high
alumina glazes cause iron to precipitate out on the surface, especially
if you cool slowly. Hence, those nice warm blushes. Calcium keeps the
iron in solution. Like where you get a good ashfall on shino, it makes
nice green runny stuff.
It would be interesting to see what a light streak of iron would do on
top of your glaze, reddish or green?
Bon feu,
Paul Herman
Great Basin Pottery
Doyle, California US
http://www.greatbasinpottery.com/
----------
>From: clennell
> I mixed my glaze today for my lipring cups and it occurred to me this might
> indeed be a real shino. I had read that shino was really mainly feldspar.
> My glaze is 80 feldspar, 10 silica and 10 quarry dust(whiting really).
> We call it our white crackle but is it not in effect a shino?
> this is a lovely fat white crackle glaze when thick on porcelain. Grey on
> stoneware.
> any thoughts?
> cheers,
> Tony
clennell on mon 3 may 04
I mixed my glaze today for my lipring cups and it occurred to me this might
indeed be a real shino. I had read that shino was really mainly feldspar.
My glaze is 80 feldspar, 10 silica and 10 quarry dust(whiting really).
We call it our white crackle but is it not in effect a shino?
this is a lovely fat white crackle glaze when thick on porcelain. Grey on
stoneware.
any thoughts?
cheers,
Tony
Tony and Sheila Clennell
Sour Cherry Pottery
4545 King Street
Beamsville, Ontario
CANADA L0R 1B1
http://www.sourcherrypottery.com
John Britt on mon 3 may 04
Tony,
Typically the shinos have no whiting as it bleaches the iron.
Usually 60 - 80 Feldspar and 40 - 20 clay. Asorted additives like
earthenware clay (from redart to Barnard), opacifiers (tin to zircopax),
soda ash or salt.
I would say that the white crackle is more of a white temmoku (in the
celadon/temmoku family), which was, if I remember, a precursor to shinos.
John Britt
Ruth Ballou on tue 4 may 04
Tony,
Louise Cort at the Freer Gallery had an analysis done of some of the old
shinos. Jim Robinson wrote an article for Studio Potter highlighting
this research. Somewhere abouts of 70 - 80% Neph Sye and 20 - 30% kaolin
will give you a shino. The high soda helps with the fire color. And you
can apply it leather hard or green. Any outgasing is a bonus.
Enjoy Japan!
Ruth Ballou
La Hulpe, Belgium
Shino Free Zone
Lee Love on tue 4 may 04
clennell wrote:
>I mixed my glaze today for my lipring cups and it occurred to me this might
>indeed be a real shino. I had read that shino was really mainly feldspar.
>My glaze is 80 feldspar, 10 silica and 10 quarry dust(whiting really).
>
>
Tony. Modern Japanese Shino is made from Hiratsu/shino feldspar.
Japanese friend once said to me, "Shino is not a glaze. Shino is a
firing method." Matsuzaki fires his shinos for almost 2 weeks.
Here is the analysis:
69.36 % SiO2
18.54 % Al2O3
6.49 % K2O
4.60 % Na2O
0.04 % MgO
0.28 % CaO
0.01 % P2O5
0.10 % Fe2O3
0.10 % MnO
0.02 % TiO2
0.45 % L.O.I.
--
Lee in Mashiko, Japan http://mashiko.org
http://potters.blogspot.com/ Commentary On Pottery
Roger Korn on wed 5 may 04
Paul Herman wrote:
...
The ones (shinos) I've used are high in alumina, from clay. I think the high
alumina glazes cause iron to precipitate out on the surface, especially
if you cool slowly.
...
This makes a lot of sense: think of the mature glaze as a mixture of
fused compounds, each with it's own solidus/liquidus transition
temperature. The glaze surface is the coolest area of the mixture while
cooling is taking place, so precipitation of compounds (FeO and Fe2O3 in
this case) from the mixture takes place there. Slow cooling allows
crystals to form and flocculate (gather into groups).
I wish I knew how to observe this phenomenon directly in real time at
the microscopic level. Ideas?
Roger
--
McKay Creek Ceramics
In OR: PO Box 436
North Plains, OR 97133
503-647-5464
In AZ: PO Box 463
Rimrock, AZ 86335
928-567-5699
Paul Herman on wed 5 may 04
Hi Roger,
Other than having a refractory microscope, looks to me like the trusty
draw trial might be the only way. A series of frozen snapshots if you
will. I think Hank has done draw rings while cooling his shinos.
best,
Paul Herman
Great Basin Pottery
Doyle, California US
http://www.greatbasinpottery.com/
----------
>From: Roger Korn
> think of the mature glaze as a mixture of
> fused compounds, each with it's own solidus/liquidus transition
> temperature. The glaze surface is the coolest area of the mixture while
> cooling is taking place, so precipitation of compounds (FeO and Fe2O3 in
> this case) from the mixture takes place there. Slow cooling allows
> crystals to form and flocculate (gather into groups).
>
> I wish I knew how to observe this phenomenon directly in real time at
> the microscopic level. Ideas?
>
> Roger
Ivor and Olive Lewis on thu 6 may 04
Dear Roger Korn,
You say <each with it's own solidus/liquidus transition temperature. The glaze
surface is the coolest area of the mixture while cooling is taking
place, so precipitation of compounds (FeO and Fe2O3 in this case) from
the mixture takes place there. >>
Am I correct in thinking that you are postulating a mixture of
separately molten compounds which crystallise independently of each
other rather than a glassy solution formed when ingredients dissolve
into the molten silicate or borate melt? An interesting idea with some
strange ramifications.
Best regards,
Ivor Lewis. Redhill, South Australia
Roger Korn on fri 7 may 04
Dear Ivor,
Not totally independent, because the crystallization/precipitation of
some higher melt compounds will bind or exclude some of the "free
silica", thus changing the composition of the remaining melt. This is a
complex situation and I'll have to delve into the energy balance aspects
of the physical chemistry of the melt to produce real world examples
that can be verified by observation. Your "... strange ramifications"
are very much how I see this, but I'll pursue it, probably in the
(Northern Hemisphere) Fall, as the building season is upon me and I am
anxious to build my new home in the high Sonoran desert and get moved
out of my cramped 28' trailer (caravan).
Trying to get my head around this notion,
Roger
Ivor Lewis wrote:
You say <each with it's own solidus/liquidus transition temperature. The glaze
surface is the coolest area of the mixture while cooling is taking
place, so precipitation of compounds (FeO and Fe2O3 in this case) from
the mixture takes place there. >>
Am I correct in thinking that you are postulating a mixture of
separately molten compounds which crystallise independently of each
other rather than a glassy solution formed when ingredients dissolve
into the molten silicate or borate melt? An interesting idea with some
strange ramifications.
Best regards,
Ivor Lewis. Redhill, South Australia
--
McKay Creek Ceramics
In OR: PO Box 436
North Plains, OR 97133
503-647-5464
In AZ: PO Box 463
Rimrock, AZ 86335
928-567-5699
Bob Ellis on tue 22 jun 04
Don't know if this would be of any interest to you shino potters, but
there is a wonderful temporary exhibition of Tomio Suzuki's work at
2000cranes.com. Recently, he's introduced something called "yo-hin shino"
(golden shino)which is just amazing. Don't know the technicals, but you
might want to surf by and take a look. Here is the URL:
http://2000cranes.com/artists_Suzuki/Shino_Exhibition_04/Online_Shino_Exhib
ition.htm
Best from the Big Apple.
B. Ellis
wayneinkeywest on tue 22 jun 04
Um, that's yoHEN shino. Isn't yohen a type of vessel? Not up on my
Japanese.
Wayne
Wayne Seidl
Key West, Florida, USA
North America, Terra
Latitude 81.45W, Longitude 24.33N
Elevation 3.1 feet (1m)
----- Original Message -----
From: "Bob Ellis"
To:
Sent: Tuesday, June 22, 2004 9:30 AM
Subject: Re: Shino anyone?
> Don't know if this would be of any interest to you shino potters,
but
> there is a wonderful temporary exhibition of Tomio Suzuki's work
at
> 2000cranes.com. Recently, he's introduced something called
"yo-hin shino"
> (golden shino)which is just amazing. Don't know the technicals,
but you
> might want to surf by and take a look. Here is the URL:
>
http://2000cranes.com/artists_Suzuki/Shino_Exhibition_04/Online_Shino_Exhib
> ition.htm
>
> Best from the Big Apple.
>
> B. Ellis
>
>
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Lee Love on wed 23 jun 04
wayneinkeywest wrote:
>Um, that's yoHEN shino. Isn't yohen a type of vessel? Not up on my
>Japanese.
>
>
Wayne, are you thinking of HENko? The Hen in HENko and yoHEN come
from two different kanji characters.
Yohen shino is fired in the yohen chamber, or "changing"
chamber. A Henko is a pot that is wider than it is deep. Some are
mold made while others are paddled.
--
Lee in Mashiko, Japan http://mashiko.org
http://journals.fotki.com/togeika/Mashiko/ Commentary On Pottery
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