Steve Slatin on mon 5 jan 04
Uranium is not available for public sale in many countries, including =
the
US, AFAIK. Naturally occurring Uranium is only 7/10 of 1 percent U-235
(the more radioactive isotope) anyway, though (except if mined in a
particular location in Gabon the name of which I cannot now remember, =
where
for fascinating but irrelevant reasons, it is even lower), and if not in
it's pure metallic state and enriched, it's quite stable. =20
Some years back I a worked for a guy who had spent a lifetime in pursuit =
of=20
better control of nuclear materials. Someone brought him an article a
poorly-informed journalist wrote suggesting that an oil drum of the
stuff was itself a potential weapon. He asked "How is it a weapon? Is
someone going to build a scaffold and drop it on people?" and he wasn't
entirely joking.
Folks often think the decay rate is such that they're at risk from even
approaching Uranium-235, but it's decay rate is very slight. Other
materials subject to decay are much riskier -- the radon in your =
basement=20
is riskier both because it's airborne and because it decays much more
rapidly. The half-life of Uranium-235 is something over 700 million =
years.
Polonium's half life is about half a year. Bismuth 210 has a half life =
of
about 5 days. Uranium-238 has a half-life in the billions of years. =
(Some
of this decay stuff is really neat -- radon-222 give up an alpha =
particle
to become Polonium-218, which has a 3-minute half life and gives up an =
alpha
to become a lead isotope, which gives up a gamma ray and a beta to =
become
bismuth-214 and so on.)
If you have any of that beautiful old yellow Fiestaware, you already =
have
some uranium. (And yes, the yellow is from Uranium.) If I had any of =
that
Fiestaware, I'd use it without hesitation. And if I had a bag of =
yellowcake
(Uranium oxide) on the shelf, I'd not have a moment's worry about it.
Uranium is pretty dull stuff.
Given the litigious nature of modern society, though, I wouldn't put it =
into
my pottery.
Steve Slatin
>I was a bit concerned by your ingredient list!!Don't you think Uranium
>might
>be a bit dangerous for just anyone to try? - mind you I'd expect it to =
be a
>tad hard to come by at your local supplier!!
>My tech lecturer was dead set against even considering it as a possible
>ingredient due to it's radioactivity....!
>Any comments folks?
>Steph
Hal Mc Whinnie on mon 5 jan 04
ARTUGAS GKAZE NUMBER 658
1250 degrees cent.
about cone7-10
spar 40
silica 25
whiting 20
epk 15
rutile 10
copper 2
cobalt 1
uranium oxide black 2
Lou Roess on mon 5 jan 04
on 1/5/04 7:35 AM, Hal Mc Whinnie at Halchaos6@AOL.COM wrote:
> ARTUGAS GKAZE NUMBER 658
>
Hal, could you maybe tell us what color these glazes are and whether they
are gloss or matt?
Lou in Colorado
Ababi on tue 6 jan 04
Hal becomes greater and greater, in other words: Hal sends us to hell...
Ababi
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Hal Mc
Whinnie
uranium oxide black 2
Hal Mc Whinnie on tue 6 jan 04
in the 1930's uranium was used in all the glaes that we value as the fiesta
ware.
it is hard to get but a wonderfull colorant.
if fired well it will not leach out into kiln.
Hal Mc Whinnie on tue 6 jan 04
these are gloss glazes for stoneware or porcelain
they tend to be in the copper blue range
Culling on tue 6 jan 04
I was a bit concerned by your ingredient list!!Don't you think Uranium might
be a bit dangerous for just anyone to try? - mind you I'd expect it to be a
tad hard to come by at your local supplier!!
My tech lecturer was dead set against even considering it as a possible
ingredient due to it's radioactivity....!
Any comments folks?
Steph
----- Original Message -----
From: "Hal Mc Whinnie"
To:
Sent: Monday, January 05, 2004 10:35 PM
Subject: glaze for week jan 5
> ARTUGAS GKAZE NUMBER 658
>
> 1250 degrees cent.
> about cone7-10
>
> spar 40
> silica 25
> whiting 20
> epk 15
> rutile 10
> copper 2
> cobalt 1
> uranium oxide black 2
>
>
____________________________________________________________________________
__
> 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.
>
Earl Brunner on wed 7 jan 04
No to what response, Hal? Without at least a part of the post you are
responding to included, this post has little meaning.
My clay experience goes back into the later half of the 60's. I mixed
tons of clay without a mask in a small storeroom, cut asbestos board
with a saber saw without a mask. We had lead oxide, and many other
chemicals that were stored and used with little to no consideration for
any hazards involved. Stirred glazes with our hands in the buckets, ALL
buckets, without consideration for what chemicals might be in them.
Fired kilns in reduction in tight, enclosed, poorly ventilated spaces.
We thought we would live forever. And we were idiots. And some of my
health problems today are a direct result.
Refusing to admit or acknowledge that this was wrong or dangerous is
foolish and irresponsible. Regardless whether one believes they should
be as extreme (or careful) as Monona Russo advocates or not, and to
reject ALL caution is foolish in the extreme. John and Ron in their
book have outlined a reasonable, logical and responsible approach. They
have NOT been alarmist, or extreme. They have issued a call for
knowledgeable potters to embrace a higher standard of professionalism
and responsibility. They suggest that those who are less knowledgeable
become more knowledgeable.
Why does this bother you? And if you want to disagree, at least provide
evidence for your arguments instead of generalities.
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Hal Mc
Whinnie
Sent: Wednesday, January 07, 2004 12:10 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: glaze for week jan 5
no
the problem is that the ware has to be well fired, yours are.
this demonstrates the degree of fear among potters now for almost any
materials.
mono russell who wrote the b ook feels that the only safe art materials
are
pencils and ink
Ron Roy on wed 7 jan 04
Hi Steph,
Your lecturer was right - not worth the candle - even if you could get it.
The danger from radio active material comes when that material is in close
contact with tissue - dust from the material in the lungs, jewelry with a
uranium glaze in contact with skin - and any dust from grinding of a glaze.
Hard stuff to get rid of once you have it - they took apart a garbage truck
that was crossing from Ontario to the US - because some human waste was
contaminated with radium treatment.
Potters used to use it - till they found out there was a danger - no
radioactive fiesta ware made now!
RR
>I was a bit concerned by your ingredient list!!Don't you think Uranium might
>be a bit dangerous for just anyone to try? - mind you I'd expect it to be a
>tad hard to come by at your local supplier!!
>My tech lecturer was dead set against even considering it as a possible
>ingredient due to it's radioactivity....!
>Any comments folks?
>Steph
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Culling on wed 7 jan 04
Steve
we were told in class that a room with a dinnerset set of Fiestaware in it
had a reading higher than the acceptable limit from the WHO so I'm not as
sure as yourself about the safety of uranium in glazes.
Steph
>>If you have any of that beautiful old yellow Fiestaware, you already have
some uranium. (And yes, the yellow is from Uranium.) <<
Catherine Yassin on wed 7 jan 04
In a message dated 1/7/2004 6:59:49 AM Central Standard Time,
culling@KISSER.NET.AU writes:
> Steve
> we were told in class that a room with a dinnerset set of Fiestaware in it
> had a reading higher than the acceptable limit from the WHO so I'm not as
> sure as yourself about the safety of uranium in glazes.
> Steph
> >>If you have any of that beautiful old yellow Fiestaware, you already have
> some uranium. (And yes, the yellow is from Uranium.) <<
>
Great. My late Grandmother collected the stuff and we've eaten off it at
her/our summer home for generations now. Wondering if I should be concerned... but
none of the recent batch of kids from my siblings nor my one seem to have any
problems. (Although my uncle is a bit of a hot head, that could be an
explanation of some serious behavior problems?) Hmmmm, and that would explain the
glow coming from the kitchen cabinets.... ;)
Seriously though... should I have the stuff tested?
-Cat Yassin
San Antonio
Steve Slatin on wed 7 jan 04
Steph --
I browsed around, but was unable to find anything useful about =
Fiestaware
radiation. I couldn't find anything; being that it's no longer
manufactured, it might be difficult to dig anything useful up.
I do not know how much actual uranium is in a square inch of glazed
Fiestaware. (If I did I might be able to calculate the actual radiation
exposure level.) I cannot imagine how it could be a significant amount,
though, given the small % of colorant in most glazes. Further, uranium
decay generates lots of particles (like alpha particles) that you have =
to
inhale to have any appreciable degree of risk. Lots of our colorants =
are
toxic if inhaled; uranium is hardly unique. And not everything that =
makes
a Geiger counter click is a serious risk.
Workers in uranium processing facilities handle enriched uranium metal
with cotton gloves. This is to protect the metal from the oils,=20
etc. on their hands. That's their protection. And they carry strips to
detect any excess radiation exposure whenever they're in the workplace, =
and
they do the work day in and day out, with far more actual metal than you
could possibly get into a glaze.
There're plenty of radioactive substances that scare me plenty. Uranium
isn't one of them. A lump of uranium, even enriched, sitting on a glove
In your hand is just a heavy piece of metal. The more 'energetic' =
metals,
even inside of a separate, inert metal containment vessel, are hot to =
the=20
touch. =20
The old orange Fiestaware is known to be a lead/uranium colorant glaze, =
and
it reputedly leaches. I'd be more worried about the lead leaching than=20
radiation from an intact glaze.
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Culling
Sent: Tuesday, January 06, 2004 11:48 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: glaze for week jan 5
Steve
we were told in class that a room with a dinnerset set of Fiestaware in =
it
had a reading higher than the acceptable limit from the WHO so I'm not =
as
sure as yourself about the safety of uranium in glazes.
Steph
>>If you have any of that beautiful old yellow Fiestaware, you already =
have
some uranium. (And yes, the yellow is from Uranium.) <<
_________________________________________________________________________=
___
__
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.
Edouard Bastarache Inc. on wed 7 jan 04
Accidental contamination from uranium compounds through contact with ceramic
dinnerware,
Ralph W. Sheets, Clifton C. Thompson
ABSTRACT: Examination of orange-colored dinnerware samples purchased in
antique stores and flea markets has revealed the occasional presence of
surface uranium compounds that are readily transferred to the hands and
clothing. We have further been able to produce soluble uranium compounds on
the surfaces of clean dishes by exposing them to household vinegar or
bleach. We estimate that handling of a contaminated dish can transfer up to
1-2 becquerels or more or uranium compounds to the hands. Uranium
contamination is of concern because the element is not only an alpha emitter
but also a chemical nephrotoxin. Although the amount of uranium likely to
be ingested as a result of casual handling may be small, it could still
exceed by several times the amount occurring in the average diet (about 40
mBq/day). Furthermore, since fresh surface compounds are readily formed, it
is possible that a person who regularly handles or eats from uranium-glazed
dinnerware can accidently ingest significant amounts of uranium.
Release of uranium and emission of radiation from uranium-glazed dinnerware,
Ralph W. Sheets, Sandra L. Turpen
ABSTRACT: Samples of orange, yellow, beige, ivory and blue-green ceramic
dinnerware glazed with uranium compounds have been examined. Measurements
at glaze surfaces yielded exposure rates of 3.8-16 mR/h (1-4 uC/kgh) for
orange glazes and rates of 0.04-1.3 mR/h (0.01-0.3 uC/kgh) for ivory, beige,
and yellow glazes. Whole body exposure from a shelf display of 40 orange
dishes was estimated to be 0.1-0.5 mR/h(0.03-0.13 uC/kgh), or up to 50 times
the room background radiation level, at a distance of 1 meter. Twenty-four
hour leaching tests of orange, yellow, and ivory dishes were carried out
with
various concentrations of acetic and citric acids. Uranium concentration in
leachates of some orange dishes exceeded 450 mg/L. Uranium is a chemical
nephrotoxin and the United States Environmental Protection Agency has
proposed
a maximum contaminant level for drinking water of 0.020 mg/L. Based on this
value a person consuming 2.2 L of drinking water per day would ingest 0.31
mg
of uranium per week. A person eating once a week from an orange glazed dish
could easily ingest 10 or more times this amount.
Later,
"Ils sont fous ces quebecois"
Edouard Bastarache
Irreductible Quebecois
Indomitable Quebeker
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
http://sorel-tracy.qc.ca/~edouardb/
http://perso.wanadoo.fr/smart2000/index.htm
http://www.digitalfire.com/education/toxicity/
Hal Mc Whinnie on wed 7 jan 04
no
the problem is that the ware has to be well fired, yours are.
this demonstrates the degree of fear among potters now for almost any
materials.
mono russell who wrote the b ook feels that the only safe art materials are
pencils and ink
Lee Love on thu 8 jan 04
Hal Mc Whinnie wrote:
>mono russell who wrote the b ook feels that the only safe art materials are
>pencils and ink
>
>
>
*Hahahaha!* Was it Karl Platt (can't remember exactly) who said to
send all your uranium to him? This topic is a periodic source of
amusement on the list.
Lee In Mashiko, Japan
http://Mashiko.us
Web Log (click on recent date):
http://www.livejournal.com/users/togeika/calendar
Earl Brunner on thu 8 jan 04
It's NOT a uranium debate Hal. We can talk about uranium until we are
blue in the face, but that's all it's going to be. Not very many of are
going to be using uranium if we WANTED to, because it is a controlled
substance. Not practical.
Nobody has suggested that the ONLY glazes we should ever use come out of
John and Ron's book. Or that all the glazes that we use HAVE to be
"stable" in quite the same way that a glaze needs to be for say, food
use. Just clearly label or describe the glaze and it's limitations.
There are some GREAT specialty glazes out there that are beautiful, and
we don't have to abandon them, we just need to use them smartly and be
aware of their limitations and risks.
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Hal Mc
Whinnie
Sent: Thursday, January 08, 2004 7:00 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: glaze for week jan 5
again this brings some sense to the unarium degbate which i am very glad
that
i started this week.
more about uranium glazes later.
i am not trying to send all of us to hell only the the heaven of really
exciting glazes.
hal
John Britt on thu 8 jan 04
I don't know if Hal was around when we discussed the Duncan recall of
their Low lead glaze which was leaching lead in excessive amounts. You can
still read about it at:
http://www.duncanceramics.com/ceramics/section.asp?SID=10
The company does not list any firing errors as the cause.
I think it is always best to reduce the amounts of toxins that we are
exposed to regardless what the "experts" say because data and testing are
always changing and improving so a substance or glaze that was
called "food safe" today may in fact be unsafe tomorrow. Education and
caution are always the best course.
I had another question about health and safety - I heard that Warren M.
had developed silicosis. Rather that spread unsubstantiated stories I
though someone on clayart would know if this is true?
I would like to do a survey sometime to see how many potters have devloped
silicosis. i Anyone has any information on this could you let me know?
Thanks,
John Britt
Hal Mc Whinnie on thu 8 jan 04
what about use for non functional work, like garden sculpture
Hal Mc Whinnie on thu 8 jan 04
again this brings some sense to the unarium degbate which i am very glad that
i started this week.
more about uranium glazes later.
i am not trying to send all of us to hell only the the heaven of really
exciting glazes.
hal
John Hesselberth on thu 8 jan 04
On Wednesday, January 7, 2004, at 03:09 PM, Hal Mc Whinnie wrote:
> no
>
> the problem is that the ware has to be well fired, yours are.
Hal,
Either I am misunderstanding your response or you are seriously out of
date. 'Well fired' does not assure that the glazes are stable. I can
show you lots of 'well fired' glazes that leach a lot of whatever is in
them when exposed to acid materials (like food). Glazes also have to
be well-formulated and not overloaded with colorants (in addition to
being 'well-fired' by which I assume you mean thoroughly melted during
firing).
I regret that you are continuing to post glazes of such questionable
properties without clear statements as to the potential problems with
them. We have a lot of people on this list who have little
understanding of glaze chemistry and I feel you are doing potters a
serious disservice by your approach. Perhaps I was wrong in an earlier
post when I said I thought you understood glaze chemistry. Are you
really just a collector of recipes? If you need help in understanding
the glazes you are posting please ask for it.
Regards,
John
http://www.frogpondpottery.com
http://www.masteringglazes.com
Hal Mc Whinnie on thu 8 jan 04
ypu have only proved my basic point.
if one handles these materials with care, which you did not do, wear face
masks, wear plastic gloves, you will advoid theses problems,
act in the glaze room as you would in a hospital
hal
Earl Brunner on fri 9 jan 04
No Hal, handling some of these materials "with care" isn't enough. We
also have to use them differently than we used to. I was introduced to
clay and all of these different materials in a different time. I used
all of the safety protocols that I was TAUGHT. And that just isn't
enough. The standards today are higher.
Why is it that you seem to think that the formulas from that period are
OK if the safety protocols from that period are not? The same thinking
that mixed clay without masks, stirred glazes with bare hands, handled
the chemicals carelessly ALSO made those recipes. Nowhere have I yet
heard you acknowledge that you need to change anything about the way you
disseminate glazes. i.e. with the necessary precautionary statements and
disclaimers, and THAT'S a;; anyone has asked you to do by the way.
Instead, you indicate distain for those who would call us to a higher
standard.
Be responsible. Surprise me.
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Hal Mc
Whinnie
Sent: Thursday, January 08, 2004 11:09 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: glaze for week jan 5
ypu have only proved my basic point.
if one handles these materials with care, which you did not do, wear
face
masks, wear plastic gloves, you will advoid theses problems,
act in the glaze room as you would in a hospital
hal
iandol on fri 9 jan 04
Dear Hal Mc Whinnie <>
You say <sculpture>>=20
Are you implying that garden decorations serve no function?? Surely you =
mean "Non Domestic"
Best regards,
Ivor Lewis. Redhill, South Australia
Ababi on fri 9 jan 04
I shall make you the most beautiful yellow glazes with titanium rutile
and iron - so way bother about uranium?
Ababi Sharon
Glaze addict
Kibbutz Shoval Israel
ababisha@shoval.org.il
http://ababi.active.co.il
http://www.matrix2000.co.nz/Matrix%20Demo/Ababi.htm
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Hal Mc
Whinnie
Subject: Re: glaze for week jan 5
what about use for non functional work, like garden sculpture
___
iandol on fri 9 jan 04
Dear Lee Love, Picked up on your response to=20
<mono russell who wrote the book feels that the =
only safe art materials are pencils and ink<
*Hahahaha!*
Got to agree with you in this day and age. Wouldn't trust pencils. =
Lethal weapons !!! And who would know about inks and the organo salts =
some of the current synthetic colours are made from.
Best regards,
Ivor Lewis. Redhill, South Australia=20
william schran on fri 9 jan 04
hal wrote: >if one handles these materials with care, which you did
not do, wear face
masks, wear plastic gloves, you will avoid theses problems,
act in the glaze room as you would in a hospital<
All well and good - if your teacher tells/shows you these, what many
of us now think of as common sense, ways to handles materials and
protect yourself.
My undergraduate teacher never did - I vividly remember adding clay
to the mixer, standing there smoking in a cloud of clay dust.
Weighing out the chemicals - bare hands, no mask - stirring it all up
with my hands.
I now wear a proper respirator, nitril or vinyl gloves (no latex in
our studio) and have appropriate tools for stirring.
Ignorance is not bliss - just leads to health problems later in life.
Bill
Hal Mc Whinnie on sun 11 jan 04
i do not think that i have to change if one will use these materials with
care.
Lori Leary on sun 11 jan 04
Hal wrote:
....i do not think that i have to change if one will use these materials with care.....
Hal,
I have been following this thread (pissing match)and it is with some impatience that I finally respond.
I'm sure these glazes of yours are beautiful and interesting. BUT....it is very irresponsible to post these recipes without any caveats or guidelines. You don't know WHO will be making these glazes, HOW they will fire them, and WHERE these glazes will end up.
Why not err on the side of caution?
Lori L.
in chilly PA.
John Britt on sun 11 jan 04
Hal,
I was wondering why all your glazes total different amounts? Like Aritgas
675 totals 119 percent, Artigas 681 totals 91 percent, Aritgas 586 totals
78 percent and then Aritgas 658 totals 100 percent.
Thanks, John Britt
Hal Mc Whinnie on mon 12 jan 04
this is the form they are given in artigas's book
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