Snail Scott on tue 30 jan 01
Has anyone ever taken one of those high-
manganese metallic glazes as low as ^1?
I've got a few variations, but generally
in the ^3-6 range. Any suggestions?
Here are two recipes. I've found nearly
identical versions of them in various
sources. These are both ^3:
42.75 Manganese
14.25 Gerstley Borate
14.25 Flint
14.25 Ball Clay
14.25 Kaolin
The same recipe can also be written:
25.00 Gerstley Borate
25.00 Flint
25.00 Ball Clay
25.00 Kaolin
plus:
75.00 Manganese
Here's a non-Gerstley variation:
48.00 Redart
36.00 Manganese
4.00 Ball Clay
4.00 Flint
4.00 Copper
4.00 Cobalt
That recipe can also be written:
85.80 Redart
7.15 Ball Clay
7.15 Flint
plus:
64.35 Manganese
7.15 Copper
7.15 Cobalt
I've still got plenty of Gerstley Borate,
and with the Gerstley version, I'd probably
just chuck in maybe 10% extra Gerstley,
and see what happens. But, I'd like to ease
away from my Gerstley-dependency problem
BEFORE I run out!
I'm not sure how to approach the Redart
version, though. I suspect that with these
recipes, the primary flux is the manganese...
Will adding more help, or is the temperature
too low? I am pretty sure that with these
glazes, the standard formulae just don't
apply.
(No! I'm not making functional ware. Most of
my sculpture scarcely has a spot you could
balance a tortilla chip on!)
I'd be grateful for any advice on how to
approach modifying this glaze.
-Snail
Liz Willoughby on tue 30 jan 01
Dear Snail,
With all the talk about manganese and the dangers to one's health,
it's hard to believe that you would print recipes using manganese in
percentages from 30 to 75 % in a glaze recipe. Doesn't matter if you
are not using it for functional ware. Someone else might. Besides
that, think of your own heath from possible inhalation from the dust
or from the fumes when firing.
I think we have to be responsible, for other's sake and for our own sake.
Defintely not a weanie,
Meticulously loose Liz
Snail wrote,
>Has anyone ever taken one of those high-
>manganese metallic glazes as low as ^1?
>I've got a few variations, but generally
>in the ^3-6 range. Any suggestions?
>
>
>I'm not sure how to approach the Redart
>version, though. I suspect that with these
>recipes, the primary flux is the manganese...
>Will adding more help, or is the temperature
>too low? I am pretty sure that with these
>glazes, the standard formulae just don't
>apply.
>
>(No! I'm not making functional ware. Most of
>my sculpture scarcely has a spot you could
>balance a tortilla chip on!)
>
>
> -Snail
>
>_________________________________________________________________________
Liz Willoughby
RR 1
2903 Shelter Valley Rd.
Grafton, On.
Canada
K0K 2G0
e-mail lizwill@phc.igs.net
Snail Scott on wed 31 jan 01
At 01:33 PM 1/31/01 -0500, you wrote:
>Who even cares if the original writer makes functional or non functual
>ware? That is like
>saying you stand in a washtub of water rather than a Jacuzzi when changing
>light bulbs!!!!HALLO!
>
>What about the potter? No way that with handling all that manganese one
>is notgoing to get a lot on self, into the studio air, onto the studio
>floor,etc.
>
Geez-
Maybe I should push it to little children,
disguised as lollipops, to improve my image!
I've worked in industrial OSHA-regulated
environments. I use a cartridge-style respirator,
gloves, hair covering, and don't even wear the
same clothes into the house afer mixing. I
fire outdoors, and I'm the only clay person I
know that owns (and uses!) kiln goggles.
My safety is my concern, and I don't take it
lightly. I mix this glaze only every few years -
I don't do tons of glazed production ware; in
fact, no functional ware at all.
I don't give this recipe out randomly (although
a nearly identical version has seen the light of
day in CM a few years back). Surely this is the
best venue to post it - where virtually all
readers could read and understand the hazards.
I appreciate the concern people have expressed
regarding health and safety, for me and others
who might use the recipe. The high-horse tone of
a few of them has been a little off-putting,
though.
Duck and Cover! -Snail
Snail Scott on wed 31 jan 01
At 10:39 PM 1/30/01 -0400, you wrote:
>Dear Snail,
>
>With all the talk about manganese and the dangers to one's health,
>it's hard to believe that you would print recipes using manganese in
>percentages from 30 to 75 % in a glaze recipe. Doesn't matter if you
>are not using it for functional ware. Someone else might. Besides
>that, think of your own heath from possible inhalation from the dust
>or from the fumes when firing.
>
>I think we have to be responsible, for other's sake and for our own sake.
>
>Defintely not a weanie,
>
>Meticulously loose Liz
>
I certainly understand your concern, Liz.
I would not put these types of glazes in a
bucket for communal studio use in a school,
for instance.
My own safety is my responsibility.
It seems to me, however, that Clayart is
the perfect venue to print the recipe,
since even a short-term subscriber could
not help but be aware of glaze-safety
issues.
Information is a good thing!
-Snail
Lili Krakowski on wed 31 jan 01
(Bless you Liz!!!)
Who even cares if the original writer makes functional or non functual
ware? That is like
saying you stand in a washtub of water rather than a Jacuzzi when changing
light bulbs!!!!HALLO!
What about the potter? No way that with handling all that manganese one
is notgoing to get a lot on self, into the studio air, onto the studio
floor,etc.
Why not just decide what effect one wants and then move on to safer ways
of getting it?
By the way: all you risk takers out there: you may think it glorious to
martyr yourself for La Causa. Please take your minds of yourselves for a
minute, and think what it wil be like for you loved ones to look
after you when you achieve your desired neurological disorder....
And if you think I'm nuts,Snail, check out a hospital or nursing ome and
see what your devilmaycare attitude can result in!!
Lili Krakowski
Snail Scott on thu 1 feb 01
At 11:15 AM 2/1/01 -0700, you wrote:
>Snail,
You posted 4 recipes with a lot
>of manganese in them and not one word of caution about how hazardous fumes
>can be from firing such glazes.
> Dave Finkelnburg
Sorry to have precipitated this little firestorm-
in-a-teapot. Since I consider most kiln fumes to
be unhealthy to some degree or another, it didn't
really occur to me to warn against manganese in
particular. (f.y.i: I fire outdoors.) David Shaner's
story is a very sad one, and I never intended to
make light of his troubles by this omission, or
to lure anyone into cavalier behavior with studio
materials. So...
DON"T SUCK KILN FUMES - ANY OF THEM!
By the way, those were only two different glazes.
I simply posted each one twice...once in the
'total to 100, plus colorants' mode, as is commonly
done, and again in the 'total (including colorants)
to 100' mode. Since the nature of these glazes is
a bit nonstandard, I wanted to present my question
in the manner most comprehensible to each reader.
I also did it to point out the ratios of the various
materials, since chemically speaking they're not
just 'base glaze + additives' formulas.
-Snail
( p.s: Even after all this discussion, I've still
only received one response to my original question!)
Paul Gerhold on thu 1 feb 01
Dear Lila,
May we also assume you don't drive a car, use any pest control chemicals,or
bleach,use artificial sweetners,eat potatoe chips, drink any alcohol with the
possible exception of red wine. And you of course do not eat red meat, or any
vegetables other than certified organic, only use cellphones with earpieces
and hold the phone a foot from your head and of course use a lead filter
between yourself and your computer screen.
Small hazards are natures way of improving the species.
Paul in Florida where it is manifestly clear that we need an I.Q. test for
potential voters and maybe potters too.
Kevin Wiberg on thu 1 feb 01
I think there's a balance between the extremes represented by Paul in
Florida and Lila regarding Manganese. I'm a little surprised by Paul's
"flippancy" considering the list had quite a discussion about Shaner and
his debilitating disease and the premature end of his active career (a
result of prolonged manganese exposure). Yes, living our lives exposes us
to all sorts of risks, but we do have choices about the level of
indifference or stupidity to which we approach these risk. Driving a car
is inherently risky. Driving after drinking is just plain stupid. Using
manganese is risky. Not protecting yourself with respirators, a
well-ventilated kiln room, etc., is just plain stupid.
Be safe,
Kevin in Vermont
At 08:34 AM 2/1/01 -0500, you wrote:
>Dear Lila,
>May we also assume you don't drive a car, use any pest control chemicals,or
>bleach,use artificial sweetners,eat potatoe chips, drink any alcohol with the
>possible exception of red wine. And you of course do not eat red meat, or any
>vegetables other than certified organic, only use cellphones with earpieces
>and hold the phone a foot from your head and of course use a lead filter
>between yourself and your computer screen.
>
>Small hazards are natures way of improving the species.
>Paul in Florida where it is manifestly clear that we need an I.Q. test for
>potential voters and maybe potters too.
>
>______________________________________________________________________________
>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.
Jonathan Kirkendall on thu 1 feb 01
Dear Liz and Lilly,
Have to say I'm with Snail on this one. There have been several glazes
posted here and in the database that ARE NOT FUNCTIONAL, and I think that's
ok.
The responsibility for using it appropriately is the potter who uses it, not
the potter who made information (like a glaze recipe) available. Snail said
very clearly that this is not a functional glaze, and that the sculptural
pieces could in no way be used as a food surface. Also, it may well be that
Snail actually uses the stuff in a VERY safe manner - perhaps it would good
to find out before assumptions are made about mixing and firing habits.
Just a thought.
Jonathan in DC
-----Original Message-----
From: Ceramic Arts Discussion List [mailto:CLAYART@LSV.CERAMICS.ORG]On
Behalf Of Snail Scott
Sent: Wednesday, January 31, 2001 12:04 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: High-manganese glazes
At 10:39 PM 1/30/01 -0400, you wrote:
>Dear Snail,
>
>With all the talk about manganese and the dangers to one's health,
>it's hard to believe that you would print recipes using manganese in
>percentages from 30 to 75 % in a glaze recipe. Doesn't matter if you
>are not using it for functional ware. Someone else might. Besides
>that, think of your own heath from possible inhalation from the dust
>or from the fumes when firing.
>
>I think we have to be responsible, for other's sake and for our own sake.
>
>Defintely not a weanie,
>
>Meticulously loose Liz
>
I certainly understand your concern, Liz.
I would not put these types of glazes in a
bucket for communal studio use in a school,
for instance.
My own safety is my responsibility.
It seems to me, however, that Clayart is
the perfect venue to print the recipe,
since even a short-term subscriber could
not help but be aware of glaze-safety
issues.
Information is a good thing!
-Snail
____________________________________________________________________________
__
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.
Cindy Strnad on thu 1 feb 01
Hello, Paul.
A high-manganese glaze isn't quite on the same order as cell phone
radiation. I agree that life is full of these little hazards. We are all
deteriorating physically from the moment we're born. But manganese isn't a
small danger. At least, not the way we use it.
Breathing the dust and fumes is the worst. I believe it is possible to use
lead, cadmium, vanadium, manganese (but maybe not practical), in a safe way.
Whether it's practical or not depends on your willingness to go out of your
way for safety, I suppose.
I'm not comfortable with using manganese in these quantities, though I
believe it's quite ethical to use it in any concentration you like on
non-food surfaces. It won't put your customers in danger that way, but you
must still see to yourself. If you have a family, you owe it to them. If
you're completely on your own, then as you wish.
Cindy Strnad
Earthen Vessels Pottery
RR 1, Box 51
Custer, SD 57730
USA
earthenv@gwtc.net
http://www.earthenvesselssd.com
Dave Finkelnburg on thu 1 feb 01
Snail,
It's good that you are setting such a fine example for studio safety and
hygiene. All of us could follow your example!
I would like to apologize to you for some of the harsh criticism you
received. Nobody on ClayArt should be abused publicly for going to the
trouble to share things with the list. Disagreed with, of course.
Discussed, quite likely. Abused, no!
Those of us who understand the hazards of manganese, especially those
who know of David Shaner's situation, are understandably emotional about
exposure to manganese fumes. I have to tell you I really cringed when I
read your post Tuesday about this subject. You posted 4 recipes with a lot
of manganese in them and not one word of caution about how hazardous fumes
can be from firing such glazes.
Please don't think later posts will correct the damage. Your post is
currently in the ClayArt archives. Anyone doing a search using "manganese"
as a keyword can pull up your post and possibly bypass any other discussion.
I know. I just tried it.
All of us, me especially, need to be cautious about what we post to the
list. It is a learning experience, though, and we can use help with the
learning process, not abuse. I do hope you keep on posting to the list. I
enjoy your observations and questions!
Dave Finkelnburg
From: Snail Scott
>I've worked in industrial OSHA-regulated
>environments. I use a cartridge-style respirator,
>gloves, hair covering, and don't even wear the
>same clothes into the house afer mixing. I
>fire outdoors, and I'm the only clay person I
>know that owns (and uses!) kiln goggles.
>My safety is my concern, and I don't take it
>lightly.
Liz Willoughby on fri 2 feb 01
Dear Snail,
I am glad that you show caution and common sense when using or mixing
a glaze that has such a high percentage of manganese. Yes, your
safety is your responsibility.
Now that I am in my 60's, I am more aware than ever that when I
started working with clay, there was next to no information available
concerning health hazards in the studio. I used to open a book, and
copy a recipe out, never thinking that any of the ingredients could
be hazardous. That is because it was never stated that any were,
except for lead and cadmium.
I guess I am beginning to feel a sense of duty, of making sure, that
potters starting out are aware of the health hazards involved in the
clay studio.
Surely it is best to try to find another material besides manganese
that might work, for the work that you do. But that is your choice.
My real concern is for those people who might use your recipes
without care.
I have recently heard of a potter friend who has had some manganese
poisoning. She used a high manganese clay body. I believe that one
of the persons who responded to this post had also had manganese
poisoning. Maybe my memory is wrong there. I think of Hans Coper,
David Shaner, if they had realized the dangers of manganese.
Certainly, I do not want for this discussion to end up with people
being abusive, that never serves any purpose, but an honest
discussion about these issues is important.
Best regards,
Liz
>
>I certainly understand your concern, Liz.
>I would not put these types of glazes in a
>bucket for communal studio use in a school,
>for instance.
>
>My own safety is my responsibility.
>
>It seems to me, however, that Clayart is
>the perfect venue to print the recipe,
>since even a short-term subscriber could
>not help but be aware of glaze-safety
>issues.
>
>Information is a good thing!
>
> -Snail
Liz Willoughby
RR 1
2903 Shelter Valley Rd.
Grafton, On.
Canada
K0K 2G0
e-mail lizwill@phc.igs.net
Ron Roy on sun 4 feb 01
I was shocked to see those recipes published without some warnings about
the hazards of MnO - yes information is a good thing - why not include it
when passing on such dangerous glazes.
I think there are still people on this list who think manganese is not a
danger - it is - and one of the worst hazards we have to deal with.
If you think you are safe outside firing these - think again - unless your
kiln is on a swivel so you can keep the wind at your back.
RR
>I certainly understand your concern, Liz.
>I would not put these types of glazes in a
>bucket for communal studio use in a school,
>for instance.
>
>My own safety is my responsibility.
>
>It seems to me, however, that Clayart is
>the perfect venue to print the recipe,
>since even a short-term subscriber could
>not help but be aware of glaze-safety
>issues.
>
>Information is a good thing!
Ron Roy
RR# 4
15084 Little Lake Rd..
Brighton,
Ontario, Canada
KOK 1H0
Residence 613-475-9544
Studio 613-475-3715
Fax 613-475-3513
Snail Scott on sun 4 feb 01
At 08:27 AM 2/4/01 -0500, you wrote:
>I was shocked to see those recipes published without some warnings about
>the hazards of MnO - yes information is a good thing - why not include it
>when passing on such dangerous glazes.
>
>I think there are still people on this list who think manganese is not a
>danger - it is - and one of the worst hazards we have to deal with.
>
>If you think you are safe outside firing these - think again - unless your
>kiln is on a swivel so you can keep the wind at your back.
>
>RR
I am aware of the fume problem - I even wear a
respirator to weld. (The bronze alloy commonly used
in art casting does contain some manganese, in
addition to the copper.)
Since I fire electrically now, I don't have to tend
the kiln as often as in my gas-firing days, and I
simply don't spend much time in the kiln yard. I
haven't begun wearing a respitator to check the kiln,
but I do hold my breath when I'm up against the
peepholes. (I'm not likely to forget, either. Some
neighborhood tomcat has claimed my kiln for his own,
and the toxic-smelling stench is a plenty strong
reminder to not inhale!) ;-)
It's certainly a valid argument, though. I remember
my school days, when we sat around the kiln yard,
drinking beer and watching all the pretty-colored
flames belching out of those big Alpines, (and the
salt kiln, and raku kiln, etc).
Now, sniffing solvents, that's my poison!
Seriously, it seemed to me that the manganese-fume
hazard had been thoroughly discussed quite recently.
Surely even a short-term subscriber would have been
aware of that discussion without redundant warnings
from me.
(Although I'll concede the 'archives' argument.)
-Snail
Ron Roy on mon 5 feb 01
The problem is not with using a manganese glaze on pots - we can handle it
when it's injested. The danger is to those who are making the ware from
dust and fumes.
If I ever post a glaze or clay body with Manganese in them I will warn
about those dangers in the same post - that way the warning stays with the
glazes in the archives.
Why not?
RR
>Have to say I'm with Snail on this one. There have been several glazes
>posted here and in the database that ARE NOT FUNCTIONAL, and I think that's
>ok.
>
>The responsibility for using it appropriately is the potter who uses it, not
>the potter who made information (like a glaze recipe) available. Snail said
>very clearly that this is not a functional glaze, and that the sculptural
>pieces could in no way be used as a food surface. Also, it may well be that
>Snail actually uses the stuff in a VERY safe manner - perhaps it would good
>to find out before assumptions are made about mixing and firing habits.
Ron Roy
RR# 4
15084 Little Lake Rd..
Brighton,
Ontario, Canada
KOK 1H0
Residence 613-475-9544
Studio 613-475-3715
Fax 613-475-3513
Lili Krakowski on mon 5 feb 01
Sorry. we all have been down that road before. What you are saying is
that because there is no vaccine for HIV people should just forget about
any and all vaccination. Wonderful!! I do drive, do no use pesticides, do
not eat potato chips, don't go near cell phones, use very little red meat.
I do take certain risks! I am sure my crib in 1930 was painted with lead
paint, that we used horible toxic stuff like potassium permanganate and
mercurochrome, that my crayons were toxic, the water pipes soldered with
lead and so on. If at 70 I eat certain things it is a risk an elderly
childless person can take. THAT NO WAY MEANS that other people should b e
exposed to that risk.
I had every chioldhood illness known to humankind. I'm fine, thank you.
But I would have my kids vaccinated, and immunized etc. Why? Becaue that
is the responsible thing to do, KNOWING WHAT WE KNOW TODAY.
Risk taking always is a question of judgment. But when your risk involves
others, you are being hostile. If you get yourself covered with MnO2 and
share it through dust on teh foor, on your clothes, on your cat, on a
shared-telephone you are infrin ging on the rights of others....
On Thu, 1 Feb 2001, Paul Gerhold wrote:
> Dear Lila,
> May we also assume you don't drive a car, use any pest control chemicals,or
> bleach,use artificial sweetners,eat potatoe chips, drink any alcohol with the
> possible exception of red wine. And you of course do not eat red meat, or any
> vegetables other than certified organic, only use cellphones with earpieces
> and hold the phone a foot from your head and of course use a lead filter
> between yourself and your computer screen.
>
> Small hazards are natures way of improving the species.
> Paul in Florida where it is manifestly clear that we need an I.Q. test for
> potential voters and maybe potters too.
>
> ______________________________________________________________________________
> 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.
>
Lili Krakowski
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