agrez on wed 16 sep 98
While reading the book "Ceramics-and how to Decorate Them" by Joan
Priolo, c. 1971, I came across the following paragraph:
"Uranium produces reds and oranges of varying shades. Between
5% and 8% is generally used to color a glaze. Too much uranium
will result in a black glaze. You may encounter some difficulty
in obtaining uranium now for the obvious reason that it is in
great demand for other less artistic, purposes."
Is it true that this was once used in glazes? When was it disallowed,
and is there a possibility that the older collectibles that I have
scattered around my house are radioactive...or is there another,
non-radioactive uranium of which I am unaware?
Regards, Andrea Grez, wondering about that black glaze covering a cute
little vase she inherited from her great aunt; thinking it might look
cuter in a lead lined box.
Marvin P Bartel on thu 17 sep 98
Is it radioactive? Yes.
Is uranium in any form safe enough for me to use? No.
There are good stains we can use that are much safer for the same colors.
We have a Fiestaware orange plate made prior to WWII. If we lay it on a
closed envelop with x-ray film inside the envelop, it takes its own
photograph in one week.
I once found a brown paper bag of uranium oxide with the other colorants in
a high school ceramics room. We tested it and the geiger counter got very
very excited.
A widow of a potter successfully brought suit against a ceramic supplier and
the supplier is now out of business becasue of one sale of uranium.
Don't be tempted unless you are a certified scientist in this area of expertise.
Marvin Bartel
http://www.bartelart.com/
At 10:14 AM 9/16/98 EDT, you wrote:
>----------------------------Original message----------------------------
>While reading the book "Ceramics-and how to Decorate Them" by Joan
>Priolo, c. 1971, I came across the following paragraph:
>
> "Uranium produces reds and oranges of varying shades. Between
> 5% and 8% is generally used to color a glaze. Too much uranium
> will result in a black glaze. You may encounter some difficulty
> in obtaining uranium now for the obvious reason that it is in
> great demand for other less artistic, purposes."
>
>Is it true that this was once used in glazes? When was it disallowed,
>and is there a possibility that the older collectibles that I have
>scattered around my house are radioactive...or is there another,
>non-radioactive uranium of which I am unaware?
>Regards, Andrea Grez, wondering about that black glaze covering a cute
>little vase she inherited from her great aunt; thinking it might look
>cuter in a lead lined box.
>
Bruce Girrell on thu 17 sep 98
Andrea wrote:
>Is it true that [uranium] was once used in glazes? When was it disallowed,
>and is there a possibility that the older collectibles that I have
>scattered around my house are radioactive...or is there another,
>non-radioactive uranium of which I am unaware?
I just had to respond to this one (see below). First, though, I can answer a
little bit. The answer is definitely Yes, uranium was once used[1]. There
are two primary isotopes of uranium U-238, the common stuff, and U-235, the
much rarer, fissionable stuff once used for an atomic bomb. Most raw uranium
oxide ore is mostly U-238 with a tiny amount U-235. It slightly
radioactivity, though. There is also some concern about radon, a decay
product of uranium and radium[4].
Probably more serious is its chemical toxcitity (Monona, are you around
today?). Uranium oxide has a chemical toxicity similar to that of lead
oxide[4].
Bottom line: Don't use it.
As far as the collectables around your house go, I wouldn't worry about
them. Since you probably don't eat out of them (they probably have lead in
the glaze as well) they present little, if any, danger to you. The degree of
radiation that you could get from one of these pieces is much less than you
would get from taking an airplane ride. Remember that many clays are
radioactive, too (potassium 40 primarily). If it really worries you, though,
borrow a geiger counter (schools often have them) and survey the objects in
your house.
The reason I had to respond is that your question reminded me of a story.
For many years, my primary source of income has been oil field related. For
the first five or so years of that career, it was my job to make
measurements on rocks in wells that had just been drilled to determine
whether or not the well would be productive. To do that we used instruments
that used gamma rays and neutrons to "see" into the rock[2]. All those who
worked anywhere near the radioactive sources were required to wear a little
badge called a "thermoluminescent dosimeter" or TLD badge as a safeguard to
let us know the level of radiation to which we were being exposed.
One time, after sending the TLD badge in for analysis, one of my coworkers
was called into the manager's office and was asked to explain what had
happened during the past month. His TLD badge showed a high radiation
dosage. Had there been an accident not reported? Had he been careless in
handling the radioactive sources? There had better be a good explanation[3]!
Try as he might, the worker could not remember anything unusual that had
happened during the previous month. Thus began a search approaching that of
an overzealous ATF raid. People with geiger counters searched his locker
area, his tool box, his car. He had to try to remember where all he had
gone. Investigators called on rather unnerved friends and relatives as well
as making semi-discreet visits to the local shops, geiger counter in hand
("Hey, buddy! Whatcha lookin for with that thing in my store?").
When they searched his house they finally found the answer. His wife had
recently been to an auction and bought a beautiful bowl which she brought
home and placed on a table near the entry door of the house. My coworker,
seeing the bowl, thought it would be a convenient place to keep his TLD
badge - right near the door, nice and handy to grab on the way to work.
Well, I'm sure you know rest of the story. The bowl was colored with uranium
and was quite capable of delivering what appeared to be a massive dose of
radiation to the sensitive TLD badge.
Thanks for triggering a fun memory,
Bruce "still glowing after all these years" Girrell
[1] In fact, you will occasionally hear of someone who still would like to
get their hands on some.
[2] No radioactive material is left behind as a result of these
measurements, should you be wondering.
[3] A high TLD reading is the trigger for a _mountain_ of paperwork.
[4] Uranium Information Centre Ltd., Melbourne, Australia
Ernesto Burciaga on fri 18 sep 98
this is what I got?? Somewhere in the depths I have a glaze formula
for uranium. I remember a bag of the stuff in school. At cone 5 it
produced a yellow. This was back in my youth, which was a long time
ago,
URANIUM OXIDE, BLACK U3O8 Uranium used as a cool yellow
colorant in glazes. In high lead, low fire (below cone 04) glazes
reds and coral red are produced in oxidization firing.
Used as uranium oxide or sodium uranate to give yellow and red
colors. Uranium reds are capable of brilliant reds in high lead
glazes with orange colors in whiteware glazes.
Ernesto
Ernesto Burciaga on fri 18 sep 98
Another ........
SODIUM DIURANATE (URANIUM YELLOW) Na2U2O7 6H2O Glaze
colorant. In a high lead glaze 5-8% will produce yellow in a low
firing temperature and oxidazitating atmosphere.
Ernesto
Rex Cornelius on fri 18 sep 98
Will look for the wonderful New Yorker article from years ago about the
California artist who needed radioactive material for a project. As I
remember it, he sought out and bought up all the red-orange Fiesta Ware he
could find... then crushed it and developed a placer / riffle technique to
separate glaze particles from body. The story was he sent the resulting
bottle of red stuff to the Atomic Energy Comission for tests. The AEC
refused to give it back to him, as too hot to be in private hands.
Also, the Lalique exhibit at the Cooper-Hewitt this summer had photos of
some very beautiful spooky yellow uranium tinted glassware which I guess
must be admired from across the room.
Could say that uranium glazes might produce glowing reviews, but I won't.
drc
=================================================================
Rex Cornelius .yaw ym ti ees ot yrT
rexc@southwind.net
=================================================================
Tom Buck on fri 18 sep 98
Agrez:
Yes, commercial uranium, if you can find it, is radioactive; it
emits alpha particles (stripped helium atoms) with a charge of 2+. Yet,
these particles compared to other radiation are quite easy to safeguard
against, the alpha particles are stopped by a sheet of paper or equal. So,
provided one doesn't use the glaze on foodware, a glaze containing Uranium
(as oxide when fired) will not be a hazard on the wall or shelf. But if
the glaze were to be used on a pot that could inadvertently end up holding
acidic food, there is a strong chance that Uranium ions could be ingested
and that would not be safe. Potters who might use Uranium should always
take steps to ensure the pot cannot hold any liquid and hence would not be
used to hold "wet" food.
As an aside, most uranium mined goes into fuel for US-style power
reactors. To be made into such fuel, the uranium is processed and split
into two types, "depleted" uranium and "enriched/fuel" uranium. Nowadays
most stains/pigments containing uranium (if available) would be made using
the depleted type with less emission of alpha particles but still
radioactive.
Tom Buck ) tel: 905-389-2339
& snailmail: 373 East 43rd St. Hamilton ON L8T 3E1 Canada
(westend Lake Ontario, province of Ontario, Canada).
Mike Lyda on sat 19 sep 98
------------------
Speaking of radioactive glaze materials...
I remember going to an exhibit at the 1984? Worlds Fair in Knoxville - =
seems
like it was regarding how safe nuclear power plants are - that had a Geiger
counter set up over a revolving table. On the table were several objects
including dirt from a local nuclear plant and a wonderful yellow plate. I =
was
fascinated by the fact that the dirt hardly registered on the Geiger =
counter,
but the plate made it go wild=21
Monona Rossol on tue 22 sep 98
---------- Forwarded message ----------
Date: Sun, 20 Sep 1998 22:54:45 EDT
From: agrez
To: CLAYART@LSV.UKY.EDU
Subject: Uranium
Resent-Subject: Uranium
----------------------------Original message----------------------------
SNIP
> Monona, I found the information you presented to be especially
> discomforting and I'm hoping that you find a publisher for Mr. Sheets'
> monograph...you might try University Graphics, a small publisher in
> Atlantic Highlands, New Jersey; I used to be a proof-reader for them a
> long time ago, and I recall that the material they published fell often
> into this category. <
Thanks for the lead. I'll track them down.
I also apologize to ClayArt. The post you read with the abstracts somehow
bounced back to me today with an error notation. I thought they didn't make
it and sent them again! Sorry.
Monona
ACTS
181 Thompson St., # 23
NYC 10012-2586 212/777-0062
Monona Rossol on tue 22 sep 98
---------- Forwarded message ----------
From: Bruce Girrell
To: CLAYART@LSV.UKY.EDU
Subject: Re: URANIUM?
----------------------------Original message----------------------------
> I just had to respond to this one (see below). First, though, I can answer
> a little bit. The answer is definitely Yes, uranium was once used[1]. There
> are two primary isotopes of uranium U-238, the common stuff, and U-235,
> the much rarer, fissionable stuff once used for an atomic bomb. Most raw
> uranium oxide ore is mostly U-238 with a tiny amount U-235. It slightly
> radioactivity, though. There is also some concern about radon, a decay
> product of uranium and radium[4]. <
Don't forget U-234. And depleted uranium is more than "slightly"
radioactive.
> Probably more serious is its chemical toxicity (Monona, are you around
> today?). Uranium oxide has a chemical toxicity similar to that of lead
> oxide[4]. <
The OSHA PELs are the same indicating they are equally controlled in the
workplace air. However, their modes of toxicity are quite different. Lead
primarily damaged the nervous system and will also ultimately harm the
kidneys. Uranium is a potent kidney toxin, and doesn't do much to the
nervous system.
> Bottom line: Don't use it. <
I second that.
> As far as the collectables around your house go, I wouldn't worry about
> them. Since you probably don't eat out of them (they probably have lead in
> the glaze as well) they present little, if any, danger to you. The degree
> of radiation that you could get from one of these pieces is much less than
> you would get from taking an airplane ride. Remember that many clays are
> radioactive, too (potassium 40 primarily). If it really worries you,
> though, borrow a geiger counter (schools often have them) and survey the
> objects in your house. >
In a previous post, I listed two papers on this subject. Now I'm going to
type in the abstracts:
Accidental contamination from uranium compounds through contact with ceramic
dinnerware, Ralph W. Sheets, Clifton C. Thompson (see earlier post for rest)
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 (rest in previous post)
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.
I ask clayarters to read this information carefully and remember
especially that Sheets found that standing 1 meter away from a display of
40 dishes increased radiation 50 times above room background. Handling
dishes transferred significant amounts of uranium. And you'd have to be
nuts to eat from them.
And we all know---if we go back into clayart archives---that there are
potters who care so little about their customers that they still use
uranium. Worse, they defend its use, make jokes about it, and convince
others that those of us who worry about such things are wimps.
I'm only sorry I didn't have access to this research when the subject came
up before.
Monona
Arts, Crafts and Theater Safety
181 Thompson St., # 23
New York NY 10012-2586 212/777-0062
http://www.caseweb.com/acts/
Monona Rossol on tue 22 sep 98
---------- Forwarded message ----------
From: agrez
To: CLAYART@LSV.UKY.EDU
Subject: URANIUM?
----------------------------Original message----------------------------
While reading the book "Ceramics-and how to Decorate Them" by Joan
Priolo, c. 1971, I came across the following paragraph:
"Uranium produces reds and oranges of varying shades. Between
5% and 8% is generally used to color a glaze. Too much uranium
will result in a black glaze. You may encounter some difficulty
in obtaining uranium now for the obvious reason that it is in
great demand for other less artistic, purposes."
Is it true that this was once used in glazes? When was it disallowed,
and is there a possibility that the older collectibles that I have
scattered around my house are radioactive...or is there another,
non-radioactive uranium of which I am unaware?
Regards, Andrea Grez, wondering about that black glaze covering a cute
little vase she inherited from her great aunt; thinking it might look
cuter in a lead lined box.
----------------------------------------------------------------------
Uranium was commonly used in glazes. Fiesta Ware and many collectible wares
are uranium glazed.
Uranium is still not banned for use in glazes, but that is because when the
Nuclear Regulatory Commission studied the problem they didn't find it in use
any more. I tried to tell them that there are tons of individual small
potteries still using uranium, but they had no way to check on the little
guys. They did ban uranium enamels because there were a lot of foreign
enameled jewelry coming into the country ticking.
And if you are looking for radioactive collectibles, take a look at glass.
Even depression glass is colored with uranium. Vaseline glass, and many
others employ uranium.
As for pottery, I refer you to two papers:
Accidental contamination from uranium compounds through contact with ceramic
dinnerware, Ralph W. Sheets, Clifton C. Thompson, The Science of the Total
Environment 175(1995)81-84
Release of uranium and emission of radiation from uranium-glazed dinnerware,
Ralph W. Sheets, Sandra L. Turpen, Department of Chemistry, Southwest
Missouri State University, Springfield, MO 65804--accepted for publication
by the Journal of Radioanal. Nucl. Chem.
And if you are truly fascinated by this problem, contact me in private and
I'll connect you up with Ralph Sheets who is the absolute expert on the use
of radioactive glazes and glass.
ANd I would like to appeal to Clayarters to help me find a publisher for a
monograph written by Ralph Sheets called: "Uranium-glazed Ceramic
Dinnerware: History, Manufacture, and Physical and Chemical Properties."
I've read all 70+ typed pages and it is super.
Monona Rossol
ACTS
181 Thompson St., # 23
New York NY 10012-2586 212/777-0062
http://www.caseweb.com/acts/
============================== End Part 3 ===============================
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