Chaeli Sullivan on fri 9 oct 09
Yes.=3DA0 But the heck of it is, everyone's fear of lead poisoning has infl=
ue=3D
nced the marketplace =3DA0so much that Amaco has removed both its Gold Lust=
re=3D
and its Bronze Patina from the market.=3DA0 Both are discontinued, suppose=
dl=3D
y because they contained lead.=3DA0 Which is a darn shame.
By the way, does anyone know of a supplier who may have some left over in s=
=3D
tock?
Chae
--- On Fri, 10/9/09, tony clennell wrote:
I've defended the use of lead glazes on this forum till I'm blue in
the face. My aunt and uncle made and sold lead glazed pots for 47
years. 12-15,000 pots per year- perfectly stable, very durable and
absolutely beautiful. Lead fuses at a very low temperature and if you
want to do some damage to yourself use a paint stripper to take the
paint off an old antique painted with lead paint.
Let's rewrite ceramic history and remove all references to lead,
barium, copper and other heavy metals.=3DA0 Let's educate people on no sex
but not good sex or bad sex.
Education not fear mongering should be the mandate of Clayart.
cheers,
Tony
http://sourcherrypottery.com
http://smokieclennell.blogspot.com
=3D0A=3D0A=3D0A
tony clennell on fri 9 oct 09
I've defended the use of lead glazes on this forum till I'm blue in
the face. My aunt and uncle made and sold lead glazed pots for 47
years. 12-15,000 pots per year- perfectly stable, very durable and
absolutely beautiful. Lead fuses at a very low temperature and if you
want to do some damage to yourself use a paint stripper to take the
paint off an old antique painted with lead paint.
Let's rewrite ceramic history and remove all references to lead,
barium, copper and other heavy metals. Let's educate people on no sex
but not good sex or bad sex.
As some of you know by my blog I am in the process of colour
investigation tutored by Robin Hopper. Many, many of my tests include
barium, lithium, copper and manganese. yesterday at school one of the
students freaked because Pete Pinnell's Celedon had 7% barium in it.
Is Pete a terrorist out to kill Americans???
Education not fear mongering should be the mandate of Clayart.
cheers,
Tony
--
http://sourcherrypottery.com
http://smokieclennell.blogspot.com
Vince Pitelka on fri 9 oct 09
Tony Clennell wrote:
"As some of you know by my blog I am in the process of colour
investigation tutored by Robin Hopper. Many, many of my tests include
barium, lithium, copper and manganese. yesterday at school one of the
students freaked because Pete Pinnell's Celedon had 7% barium in it.
Is Pete a terrorist out to kill Americans???
Education not fear mongering should be the mandate of Clayart."
Dear Tony -
Thank-you for that sensible post. Barium, lithium, manganese, copper, and
even LEAD can be used perfectly safely with the appropriate precautions. I=
n
an institutional situation I think that lead should only be used as a
fritted lead silicate. Otherwise, barium carbonate, lithium carbonate,
manganese dioxide, and copper carbonate and oxide can all be used very
safely. This is about education and safety, not materials censorship.
Banning supposedly "dangerous" materials from the glaze lab is a little bit
like banning supposedly "dangerous" thinking and speaking from society.
- Vince
Vince Pitelka
Appalachian Center for Craft
Tennessee Tech University
vpitelka@dtccom.net; wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka
Edouard Bastarache on fri 9 oct 09
"Education not fear mongering should be the mandate of Clayart.
Tony"
That is what I have been trying ro do here for years,
Gis,
Edouard Bastarache
Spertesperantisto
Sorel-Tracy
Quebec
http://edouardbastarache.blogspot.com/
http://substitutions.blogspot.com/
http://www.flickr.com/photos/30058682@N00/
http://albertpaintings.blogspot.com/
http://cerampeintures.blogspot.com/
ivor & olive lewis on sat 10 oct 09
Tony is right, there is a paranoia about the dangers of materials.
Those who wish to raise the issue might consider using correct terminology
for the ingredient they are maligning, or the name of the mineral from whic=
h
the chemical is derived, or the common place name of the chemical. If you d=
o
not know these, name the element and make it generic by saying "Compound"
eg...Lead Compound...Cadmium Compound....Copper Compound
The very first glaze I ever made was composed of equal parts Red Lead and
clay. It was Lead Oxide, Pb3O4. I could have used Galena, a natural mineral
composed of Lead Sulphide. Powdered, this material is dusted onto wet pots.
There is also a yellow lead oxide called Massicot as well as a white powder
called White Lead which is a basic carbonate. To overcome workplace hazard
for potters there are two "frits", Lead Sesquisilicate and Lead Bisilicate.
Today I would be a little more systematic by making a frit of one Mol of
Lead Oxide, two mols of Silica and one tenth of a mol of Aluminium hydrate.
Since the invention of the Automobile the greatest threat of Lead Poisoning
has been from the exhaust of vehicles burning Leaded Gasoline (Tetra-ethyl
Lead). So what did they do, gave us unleaded with a Manganese anti-knock
additive ! ! !
Best regards,
Ivor Lewis,
Redhill,
South Australia
Bonnie Staffel on sun 11 oct 09
When I visited China back in the early 80s we were given a tour of the
different factories where they famous lead glazed colorful horses were =3D
being
decorated. We went into a room lined with tables with young girls =3D
sitting
next to each other and with a horse statue in front of each. These girls
were painting on the red lead glaze. They were drinking tea along with =3D
their
work. On the floor was a heavy coating of red lead which had fallen from
their worktables. I didn't see any ware boards so each statue was moved =3D
or
carried by hand over to the shelf before loading into a kiln. When I =3D
asked
about the dangers of using the red lead in this way, the answer came =3D
down to
that the painters were expendable. I found that this attitude was used =3D
in
other craft work we were shown on the tour. The silk embroiderers were =3D
doing
very fine sewing and the answer there was after a few years their eyes =3D
would
give out and they would have to do another job. Another expendable use =3D
of
their citizens: girl babies were also expendable so the family that was
allowed by decree only one child, waited for a boy.=3D20
My quarrel with the use of lead is the misuse. I used white lead in my =3D
early
glazes but did not know that fumes from the kiln were also lead laden. =3D
My
kiln was in the basement of our house. One of my potter friends was =3D
teaching
a class and someone forgot to turn on the fan in the spray booth. The =3D
room
was filled with the lead contained glaze dust. My friend went in and =3D
turned
on the fan and had everyone leave the room. She wound up in the hospital =
=3D
but
luckily recovered.=3D20
Judging from the innocent questions of the newbies on the forum, giving =3D
the
green light to these potters to use lead based glazes could be very
dangerous. IMO even the encapsulated lead must give off fumes when =3D
melted as
a glaze when fired.
Bonnie=3D20
http://webpages.charter.net/bstaffel/
http://vasefinder.com/bstaffelgallery1.html
DVD=3DA0 Throwing with Coils and Slabs
DVD=3DA0 Introduction to Wheel Work
Charter Member Potters Council
Lee Love on sun 11 oct 09
On Sun, Oct 11, 2009 at 7:14 AM, Bonnie Staffel wr=
ote:
> Judging from the innocent questions of the newbies on the forum, giving t=
he
> green light to these potters to use lead based glazes could be very
> dangerous. IMO even the encapsulated lead must give off fumes when melted=
as
> a glaze when fired.
I am with you Bonnie. I don't like alarm-ism, but I also think a
flippant attitude about chemicals to beginners is not professional.
These materials can be used safely by folks who know how to used them,
but I would keep them out of communal or group situations until the
fledgling potter knows what they are doing.
My teacher used lead based enamels safely for years, but I
would not recommend them to folks that don't know what they are doing.
--
Lee Love, Minneapolis
"The tea ceremony bowl is the ceramic equivalent of a sonnet: a
small-scale, seemingly constricted form that challenges the artist to
go beyond mere technical virtuosity and find an approach that both
satisfies and transcends the conventions." -- Rob Sliberman
full essay: http://togeika.multiply.com/journal/item/273/
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