Chris Stanley on tue 9 sep 03
We have examples of plaster being used as far back as 6000 BCE in Neolithic
Jericho. I would assume from finds at places like Catal Huyuk that Plaster
had been around for awhile before 6000 BCE.
Here are some notes from a lecture on molds.
?The Oldest Traces of Plaster Renders Are 9,000 Years Old, and Were Found
in Anatolia and Syria. We Also Know That 5,000 Years Ago, the Egyptians
Burnt Gypsum in Open-air Fires, Then Crushed It Into Powder, and Finally
Mixed This Powder With Water to Make Jointing Material for the Blocks of
Their Monuments, Such As the Magnificent Cheops Pyramid for Example. The
Ancient Egyptians Used Models of Plaster Taken Directly From the Human Body.
An article in Science Magazine makes a startling suggestion as to where this
social cohesion came from. The soil just under the marshes surrounding
Çatalhöyük was rich with a chalky marl. It may be mixed into a clay-like
mud, which we could call plaster. Plaster made its houses. Wall frescos were
painted upon plaster. The people of Çatalhöyük appear to have been drawn to
the artistic and technical possibilities of a new building material.
What an unnerving idea, that the binding social fabric of this remarkable
early city should be nothing more grand than -- plaster.
Paul Lewing on tue 9 sep 03
Another history question, guys.
Does anyone know when, where, and by whom plaster of Paris was invented, and
when potters first started to use it for molds? And when slipocasting was
invented?
Of course, before that, all pots were "handmade". After that, we all got to
start arguing about what was handmade and what wasn't.
Paul Lewing, Seattle
Louis Katz on wed 10 sep 03
Here is my question. Are you sure that frescoes are done on plaster of
paris plaster, or are they done on lime plaster?
I have no doubt that plaster of paris plaster is old, but i read lots
of confusing things about "plaster".
The word plaster seems to mean any sticky mud applied as a covering
hence "apply a mustard plaster".
Louis
On Wednesday, September 10, 2003, at 02:42 PM, Marcia Selsor wrote:
> Plaster must have been pre-Roman. I saw some frescoes from 500 BC in
> Armenia, north of Iran. Frescoes are plaster. But I don't know when
> they
> started using plaster for molds. Also, weren't the Minos frescoes 1400
> BC?
> Marcia Selsor
> 2 days left before we leave!!
> --
> Tuscany 2004
> http://home.bresnan.net/~m.selsor/Tuscany2004.html
>
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Diana Pancioli on wed 10 sep 03
I am curious about his too Paul.
I know that they used biscuit molds before plaster.
I think the Romans were still using biscuit molds in the first century.
Diana
Marcia Selsor on wed 10 sep 03
Plaster must have been pre-Roman. I saw some frescoes from 500 BC in
Armenia, north of Iran. Frescoes are plaster. But I don't know when they
started using plaster for molds. Also, weren't the Minos frescoes 1400 BC?
Marcia Selsor
2 days left before we leave!!
--
Tuscany 2004
http://home.bresnan.net/~m.selsor/Tuscany2004.html
Kathie Wheater on wed 10 sep 03
Hello Mister Lewing,
a quick search came up with this.
Were did plaster of paris originate?
Reminds me of the time Olive (a goofy blonde like myself) called to
ask, " Kathie how long do you cook minute rice?"
The term came from the fact that the walls of all homes in Paris were
to be protected with plaster in reaction to the Great Fire of London in 1666.
Calcined gypsum was used bt the early Egytians in their construction.
They used this plaster for lost wax casting as well.
KathieW
who's dog dresses better than she
Betsy looks divine in a pink feather boa and pearls
I think Emma had something to do with this
Another goofy blonde
Marcia Selsor on thu 11 sep 03
Louis Katz wrote:
> Here is my question. Are you sure that frescoes are done on plaster of
> paris plaster, or are they done on lime plaster?
> I have no doubt that plaster of paris plaster is old, but i read lots
> of confusing things about "plaster".
> The word plaster seems to mean any sticky mud applied as a covering
> hence "apply a mustard plaster".
> Louis
Good point. But lime plaster should be processed the way plaster of
paris is porcessed. I can't say what mustard plaster is. Frescoes that I
have seen seem to be a lime plaster based and very white. Is this sticky
mud substance used for painted ornamentation on walls?
Marcia Selsor
Tuscany 2004
http://home.bresnan.net/~m.selsor/Tuscany2004.html
Stephani Stephenson on thu 11 sep 03
Paul and all,
The Firth book on 'Mold making for the Ceramic Artist' has a
good history of plaster and molds. Also a great background
on how plaster is made, etc. I have the newer paperback
edition. My copy is at the studio. I will fetch it and
report back! (rather than trying to paraphrase from memory
tonight.) I do remember he talks at length on Roman
developments of the techniques.
An interesting quote from Chapter 1, 'Prehistoric Ceramics
from the Beginning to 2500 B.C.," from the book "World
Ceramics from Prehistoric to Modern Times" by Hugo and
Marjorie Munsterberg, 1998, states that
"All evidence points to a variety of ways in which the
technology of working clay was turned to the making of
vessels and containers. Pots could be shaped by the pinching
of wet clay with fingers, by placing coils of clay on top of
one another and then smoothing the sides, by building with
slabs, or by using preformed molds either inside or outside.
"
This comment is a huge tease though, because so little
information is given about the materials used in making of
molds, even when use of molds is cited, in many sources of
reference.
NOTE on following : I am not a historian or expert in these
matters, am just doing some quick excerpting....so take
it for what it is
The ancient city of Jericho 5th millennium B.C. :
human skulls which have been overcoated or 'reconstituted'
with plaster, to form plaster portraits: facial features ,
musculature modeled, in plaster, painted,..shells inlaid
over eye sockets, etc..Plaster relief work. and walls of
homes coated...probably with lime plaster..
Egypt: ,
Excavation of the workshop of the sculptor Tuthmosos, who
lived in Armara , shows that, in preparation for completion
of portraits, he took plaster molds from both living and
dead models. 1370 B.C. an example of a death mask taken from
such a mold is the death mask of Amenhotep III, now in the
Staatliche museum in Berlin. The mask as well as the mold
in plaster.
A photo of it is in the same source where I got some of this
information, "The History of world Sculpture", by Germaine
Bazin. Egyptians also used plaster in some relief friezes
on walls, but I do not know during which time period, etc.,
see reference below to differences between use of gypsum
plaster and lime plaster....
Other tidbits:
uses of plaster in sculpting and modeling, Mycenaean,
painted plaster heads circa 13th c. B.C.
frescoes, or fresco secco, where pigment is applied later to
a lime plaster wall coating. some surviving remnants from
early Minoan house walls, first palaces of Knossos and
Phaestos, 2000-1700 B.C., and many surviving examples from
1550 and 1450 B.C.
examples of near east , plastered walls, etc. from many
areas of Mesopotamia, probably lime plaster .
molds: Crete: 15th and 16th Centuries B.C. Terra Cotta
rhyton in the form of a bull, dated between 1450 and 1550
B.C. mold made, but this source does not describe the mold
material. Notes that this is the first recorded use of the
mold in this part of the world for terra cotta figures, and
states that it appears that there is a subsequent gap of
600-700 years, before existing evidence shows this type of
practice resuming.
Also the history of the fabulous plasterwork in the near
eastern and Islamic or Moorish cultures... examples in the
Alhambra, etc.
.Lime plaster was used to protect buildings in the near and
middle east. Gypsum plaster, also referred to as stucco, was
carved, modeled and molded to produce 3D forms, sometimes
the forms made over a wooden lathe frame, then carved in
situ. Also gypsum plaster used to fix small pieces of
mosaic.
I have read that Early Islamic pottery for daily use was
made from clay turned on the wheel and then often pushed
into a mold when relief decoration was desired, a techniques
using both the wheel and molds... again no description of
the mold or material...
Central highlands Mexico: Teotihuacan I-II, 200 B.C. to 200
A.D., plaster used on wall frescoes, described as true
frescoes. Molds used in making of pottery, for "production
both of figures and of the projecting borders of cylindrical
vessels which were often decorated with a frieze of small
heads of gods."
The author goes on to say that the use of molds gives
evidence of the culture's gradual decline, (ah, do I sense
Vince smiling??!), as in some areas, even the finishing
touches made by hand began to disappear...by the time of
Teotihuacan IV , molds remained but style is considered
"enervated, decadent and devoid of conviction" (though I do
wonder at the process by which historians are able to deduce
and comment on these things, and leave social bias aside...
also no mention of mold material
I have not read the entire book yet )
Later, in describing changes in Aztec pottery, the authors
also decry not only the use of molds but part timers!
"The crisis that came about in Aztec potter had already
begun at the time of the late Teotihuacan culture. Leading
up to it was the growth of population in the large centres,
and the point of crisis was reached when ceramic art went
over to mass production. Hundreds, even thousands, of small
votive figurines were produced from the same moulds.
Nevertheless, even during the period of urban quantity
production, there still appeared articles of the highest
quality, (although these are attributed to the Mixtecs, or
else to strong Mixtec influence)....(also talks a bit about
Incas)
...."Under militaristic regime of the Peruvian monarchs and
of the Aztec rulers alike, the ceramics skills of preceding
cultures languished. Pottery seems to have been the province
of part- time craftsmen, not full time professionals"
I am throwing the above quote in , for perspective and
because the it almost seems.... the joke is on us.....
La Mixteca Alta... Mixtec people were proficient
metalworkers and practiced lost wax casting with
gold....molds were of clay, Mixtec pottery also made, and
very highly esteemed.. Huaxtec , people who had lived on
Gulf coast of today's Mexico, used baked clay for building
material, and coated ceremonial areas with lime plaster,
gotten from seashells, and painted them brilliantly...
evidently excavation in this area had just begun in 1969,
which is the year of the book I am skimming for a lot of
this info , called 'Ancient Mexican Art", by Ferdinand
Anton, translated from the German
' Alt Mexiko und sein Kunst, by Betty and Peter Ross,
published by Thames and Hudson Ltd
Bronze casting: China:
During Xia dynasty 2100 -1600 BC and Shang dynasty 1600 BC
to 1050 BC, Clay was used for molds in casting bronze, clay
also for molds in Classical Greek bronzes, Viking and early
scandinavian cast metal. Stone molds used in very ancient
cast metal, as in spear points, in old Europe....I wonder
where in the history of casting metal, plaster based
aggregates came into use as mold material?
It is fascinating to me that knowledge and use of plaster
exists as a primary material alongside direct and mold
based forming methods with clay, metal, glass... yet it
seems difficult to determine , at least from all these
secondary sources, when, where and whether the use of
plaster crossed over, from being used as a direct covering
and modeling material to a mold making material
Following are two sites...one talks about the differences of
gypsum v. lime plaster in traditional uses.... another gives
a very interesting description of the traditional techniques
of making and applying Qudad, Yemeni lime plaster, as a
weather proof coating for buildings and homes.
http://www.aiys.org/webdate/qudad.html
http://www.buildingconservation.com/articles/gypsum/gypsum.htm
Stephani Stephenson
steph@alchemiestudio.com
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