Geoff Graham on mon 12 jun 06
I am a new subscriber.
I've joined with a specific question.
I have done a lot of experimenting with imitating ancient Greek pottery
using Newman Red terra sigillata on the ground of the vessel and various OM4
terra sigillatae stained with oxides. My results are mixed: while I have
fairly good design work (the best that one can expect in an amateurish,
modern imitation), the technical materials are failing to live up to their
ancient models.
Black iron oxide gives too brown of a color.
Manganese oxide gives too grey of a color.
Cobalt oxide helps to blacken the aforementioned stains, but really not
adequately, and eventually with too many oxides, the terra sigillata becomes
impossible to burnish, not to mention that the oxides smear around when
trying to burnish them.
I have gotten fairly nice black using mason stain, but once again, the slip
can no longer take a shine really.
I saw some archived ClayArt posts where others discussed the issue of
reproducing Attic black "glaze." I was particularly interested to see the
posting by Eleni Aloupi. I was very interested to hear that so many people
have attempted unsuccessfully to reproduce these effects.
Right now I am just about ready to give up on trying to do anything on
burnished terra sigillata, and move toward finding glazes which might be
able to approximate the look of Attic figure ware. The necessary parameters
for success would be that the glaze would not tend to run, that very thin
line drawings using the glaze could successfully be executed, and that it
would be matchable to a red surface which should shine somewhat as well as
the black glaze. That, I realize, is a very tough order, but I'm not quite
ready to give up yet.
Does anyone have any suggestions along either line:
A. something that will work for the terra sigillata approach? A different
base clay? A different oxide or stain? Adding some glassy additive?
OR
B. something that could work in a glazing approach? Black glazes that can
be applied very thinly in hairline strokes, and which will not run on the
surface of another glaze? What kind of surface glaze could have a nice
orangy color, a satiny finish, and not run too terribly?
Thank you very much for any information you may be willing to share.
Geoff Graham
Ukiah, California
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Janine LaMaie on tue 13 jun 06
Hi Geoff:
Not sure if this will lead anywhere, but have you considered a red clay
body and black engobe overall then sgraffito? I find it easier to get fine
detail with an incising tool than with a brush. I have used a premixed
black engobe by Clay Art Center in Tacoma that's truly black. It's one of
a line called "Fireshades" and it holds up to at least cone 7. (If you're
using burnished terra sig, you're probably firing lower than that.) Looks
nice under satin matte transparent glaze. You just need to take care with
any flakes generated in the sgraffito process that might land where you
don't want them - like I said, this product is BLACK. I use on leather
hard greenware. Never tried to burnish, I have a feeling the black would
smear. Best of luck in your efforts to create the Attic black look. Do
you make the classic shapes that this decoration method traditionally
adorns?
Cheers!
Janine LaMaie
Tacoma, WA
Malcolm Schosha on tue 13 jun 06
Geoff,
It is known that the black in Attic Greek pottery was produced with the
same red clay with which the pot was thrown. They added no pigments to
produce the black. But the clay used for painting was much more highly
refined, that is smaller particle size.
In the firing, the pots were 1.fired in oxidation, 2.then heavily reduced,
3.then returned to oxidation. In step 1 the whole pot was, of course, red.
In step 2 the whole pot was black. In step 3 the body to the pot returned
to red, but the finer particles of the painted surface sintered and
remained black.
Malcolm
On Mon, 12 Jun 2006 21:34:40 -0700, Geoff Graham
wrote:
>I am a new subscriber.
>
>I've joined with a specific question.
>
>I have done a lot of experimenting with imitating ancient Greek pottery
>using Newman Red terra sigillata on the ground of the vessel and various
OM4
>terra sigillatae stained with oxides. My results are mixed: while I have
>fairly good design work (the best that one can expect in an amateurish,
>modern imitation), the technical materials are failing to live up to their
>ancient models.
>
>Black iron oxide gives too brown of a color.
>
>Manganese oxide gives too grey of a color.
>
>Cobalt oxide helps to blacken the aforementioned stains, but really not
>adequately, and eventually with too many oxides, the terra sigillata
becomes
>impossible to burnish, not to mention that the oxides smear around when
>trying to burnish them.
>
>I have gotten fairly nice black using mason stain, but once again, the slip
>can no longer take a shine really.
>
>I saw some archived ClayArt posts where others discussed the issue of
>reproducing Attic black "glaze." I was particularly interested to see the
>posting by Eleni Aloupi. I was very interested to hear that so many people
>have attempted unsuccessfully to reproduce these effects.
>
>Right now I am just about ready to give up on trying to do anything on
>burnished terra sigillata, and move toward finding glazes which might be
>able to approximate the look of Attic figure ware. The necessary
parameters
>for success would be that the glaze would not tend to run, that very thin
>line drawings using the glaze could successfully be executed, and that it
>would be matchable to a red surface which should shine somewhat as well as
>the black glaze. That, I realize, is a very tough order, but I'm not quite
>ready to give up yet.
>
>Does anyone have any suggestions along either line:
>
>A. something that will work for the terra sigillata approach? A different
>base clay? A different oxide or stain? Adding some glassy additive?
>
>OR
>
>B. something that could work in a glazing approach? Black glazes that can
>be applied very thinly in hairline strokes, and which will not run on the
>surface of another glaze? What kind of surface glaze could have a nice
>orangy color, a satiny finish, and not run too terribly?
>
>Thank you very much for any information you may be willing to share.
>
>Geoff Graham
>Ukiah, California
Snail Scott on wed 14 jun 06
At 09:34 PM 6/12/2006 -0700, you wrote:
>...imitating ancient Greek pottery
>using Newman Red terra sigillata on the ground of the vessel and various OM4
>terra sigillatae stained with oxides.
>Black iron oxide gives too brown of a color...
My memory agrees with Malcolm's statement:
those black-on-red pieces were made of one
color terra sig; the 'black' designs were
of a slightly different composition (finer,
or maybe slightly fluxed) and acted as a
carbon trap during those low temperature
firings. One of the reasons that researchers
believe this is the discovery of 'seconds'
in which the painted patterns retained (or
regained) their original red color in places,
from a firing gone wrong.
This theory explains the pure blackness of
the color, but it will be very difficult to
reproduce without a similar firing practice.
Even in period, they obviously couldn't get
it right every time; I suspect you will have
a whole lot of experimenting to do, to get
the right smoke levels, and the right
temperatures, in addition to getting the
right terra sig.
So, how closely do you want to emulate this
stuff? If it's only the look you want, I
suspect paint will be more effective than a
ceramic process. If it's the process that
interests you, you may face a lot of not-
quite-right results to get there.
-Snail
>
>Manganese oxide gives too grey of a color.
>
>Cobalt oxide helps to blacken the aforementioned stains, but really not
>adequately, and eventually with too many oxides, the terra sigillata becomes
>impossible to burnish, not to mention that the oxides smear around when
>trying to burnish them.
>
>I have gotten fairly nice black using mason stain, but once again, the slip
>can no longer take a shine really.
>
>I saw some archived ClayArt posts where others discussed the issue of
>reproducing Attic black "glaze." I was particularly interested to see the
>posting by Eleni Aloupi. I was very interested to hear that so many people
>have attempted unsuccessfully to reproduce these effects.
>
>Right now I am just about ready to give up on trying to do anything on
>burnished terra sigillata, and move toward finding glazes which might be
>able to approximate the look of Attic figure ware. The necessary parameters
>for success would be that the glaze would not tend to run, that very thin
>line drawings using the glaze could successfully be executed, and that it
>would be matchable to a red surface which should shine somewhat as well as
>the black glaze. That, I realize, is a very tough order, but I'm not quite
>ready to give up yet.
>
>Does anyone have any suggestions along either line:
>
>A. something that will work for the terra sigillata approach? A different
>base clay? A different oxide or stain? Adding some glassy additive?
>
>OR
>
>B. something that could work in a glazing approach? Black glazes that can
>be applied very thinly in hairline strokes, and which will not run on the
>surface of another glaze? What kind of surface glaze could have a nice
>orangy color, a satiny finish, and not run too terribly?
>
>Thank you very much for any information you may be willing to share.
>
>Geoff Graham
>Ukiah, California
>
>_________________________________________________________________
>Express yourself instantly with MSN Messenger! Download today - it's FREE!
>http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/
>
>___________________________________________________________________________
___
>Send postings to clayart@lsv.ceramics.org
>
>You may look at the archives for the list or change your subscription
>settings from http://www.ceramics.org/clayart/
>
>Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
>
Vince Pitelka on wed 14 jun 06
Geoff -
This all depends on how authentic you want to be. In his tongue-in-cheek
take-offs on red-black attic painted pottery, Michael Frimkess just used
underglazes. You can get a good black slip and iron red slip using oxides,
but that's not how the Greeks did it. I think that both Malcolm and Snail
have already posted on this. Years ago I read a book that described the
technique in detail - I believe the title was "Techniques of Attic Painted
Pottery" or something close to that.
As I understand it, both the red and the black come from terra sigillatas of
identical composition except that the black terra sig was prepared with
water derived from soaking wood ashes - in otherwords, it contains soluble
alkaline fluxes. The wares were fired in updraft kilns, and a series of
"draw trials" with black and red decoration were placed inside a small port
near the top of the kiln. As the kiln approached maturity in a reduction
atmosphere, all slip would turn black, as the red iron oxide was reduced to
black iron oxide. The potter would start pulling draw tiles periodically,
and would check to see if the red sig re-oxidized to red while the fluxed
black sig remained black. If a tile was pulled too early, both sigs would
re-oxidize to red. If the firing was stopped at the right time, the
un-fluxed red terra sig would re-oxidize to red, while the fluxed black sig
would be vitrified, and the black color would be locked in place, unable to
reoxidize. If the wares were overfired, even the red sig would vitrify, and
nothing would re-oxidize to red. Snail mentioned the examples of "mistakes"
that can be found in museums, where the whole surface is black and only the
faintest outline of the design is visible.
Good luck -
- Vince
Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
Karin Hurt on thu 15 jun 06
I found this site on the subject
http://www.cm.aces.utexas.edu/faculty/skrukowski/writings/pots.html
Vince Pitelka wrote:
Geoff -
This all depends on how authentic you want to be. In his tongue-in-cheek
take-offs on red-black attic painted pottery, Michael Frimkess just used
underglazes. You can get a good black slip and iron red slip using oxides,
but that's not how the Greeks did it. I think that both Malcolm and Snail
have already posted on this. Years ago I read a book that described the
technique in detail - I believe the title was "Techniques of Attic Painted
Pottery" or something close to that.
As I understand it, both the red and the black come from terra sigillatas of
identical composition except that the black terra sig was prepared with
water derived from soaking wood ashes - in otherwords, it contains soluble
alkaline fluxes. The wares were fired in updraft kilns, and a series of
"draw trials" with black and red decoration were placed inside a small port
near the top of the kiln. As the kiln approached maturity in a reduction
atmosphere, all slip would turn black, as the red iron oxide was reduced to
black iron oxide. The potter would start pulling draw tiles periodically,
and would check to see if the red sig re-oxidized to red while the fluxed
black sig remained black. If a tile was pulled too early, both sigs would
re-oxidize to red. If the firing was stopped at the right time, the
un-fluxed red terra sig would re-oxidize to red, while the fluxed black sig
would be vitrified, and the black color would be locked in place, unable to
reoxidize. If the wares were overfired, even the red sig would vitrify, and
nothing would re-oxidize to red. Snail mentioned the examples of "mistakes"
that can be found in museums, where the whole surface is black and only the
faintest outline of the design is visible.
Good luck -
- Vince
Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
______________________________________________________________________________
Send postings to clayart@lsv.ceramics.org
You may look at the archives for the list or change your subscription
settings from http://www.ceramics.org/clayart/
Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
Thank You,
Karin Hurt
www.laughingbearpottery.com
Arizona
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