Ivor and Olive Lewis on fri 11 jul 08
Dear Vince,
I do not have access to the archives of those companies or
institutions that may have done this research.
Frank Hamer is silent on the matter. So are Felix and Sonya Singer.
Hence, your opinion <<... if there was even the slightest danger of
craze cracks
harbouring dangerous bacteria we would all know about it. ...>> seems
to be upheld, since nothing is said about the possibility of such a
hazard in either text.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
Steve Slatin on fri 11 jul 08
Ivor -- Vince --
I know this can be taken as argumentative,
but I find myself compelled to say it anyway.
The fact that there is no record of a test
being made and having a positive result
does not prove that there was a test and
the result was negative. Saying that it's
so is, in fact, somewhat illogical.
The truism is "absence of evidence is not
evidence of absence." Let's fill this in
-- Absence of evidence that crazed ware is
unsafe is not evidence that crazed ware
is safe. The inverse is likewise true --
Absence of evidence that crazed ware is
safe is not evidence that crazed ware is
unsafe.
In the absence of evidence that the safety
of crazed ware has ever been tested, it is
not possible to conclude that crazed ware
has been tested and proved safe.
We can apply what we do know to probability
of risk. We do know that it's somewhat
harder to clean crazed ware -- that's why
heavily crazed ware retains the aromas of foods
when uncrazed ware does not.
We also know that very high temperature
cleaning (steam especially) will eliminate
these aromas in many cases. Clearly, this
indicates that whatever risks to remain
are somewhat attenuated by very high temperature
cleaning. The probability of risk with
crazed ware can be reduced with more
careful cleaning.
Has crazed ware been used for hundreds
-- even thousands -- of years? Yes!
And in most of those years, people got
sick from food-related illnesses regularly
and died young. Can we 'prove' that this
was related to crazed ware? No.
But put a nice bit of smoked halibut
on two plates, one visibly crazed, one
not, and leave them to sit for a few
hours. Come lunch time, consume the
halibut. (Not a required part of the
test, but the best part.) Wash both
in the same fashion, detergent, water
(not to hot to wash by hand), and dry
(use different towels for each).
Sniff them both. Do they smell
different? If they do, you've
established that using your processes,
there is a difference between the two.
(The test can be made better by having
a disinterested party, unaware of the
nature of the test or the difference
between the two plates, do the sniff
test. Better still to have a third
disinterested party do the washing,
likewise unaware of the issues.)
For myself, I am always very
concerned with a presumption made
on the basis of the theory that
"they" must have already checked
it and found it safe. If there's
anything we learn from perusing the
daily news, it's that "they" are a
lot dumber than they look, and
rarely investigate anything until
after there's an outbreak of trouble.
Climbing down from the soapbox --
Steve Slatin
--- On Thu, 7/10/08, Ivor and Olive Lewis wrote:
> > Dear Vince,
> I do not have access to the archives of those companies or
> institutions that may have done this research.
> Frank Hamer is silent on the matter. So are Felix and Sonya
> Singer.
> Hence, your opinion <<... if there was even the
> slightest danger of
> craze cracks
> harbouring dangerous bacteria we would all know about it.
> ...>> seems
> to be upheld, since nothing is said about the possibility
> of such a
> hazard in either text.
> Best regards,
> Ivor Lewis
Ron Roy on wed 16 jul 08
I must say I think Steve has made some very important points here.
Why do so many potters think that crazed ware is nothing to complain about?
Surely there are obvious and compelling reasons that uncrazed ware is
superior - for many reasons.
Why are there government rules about this for restaurants?
Are we - as a group - simply not capable of solving the problem or just not
interested?
RR
>I know this can be taken as argumentative,
>but I find myself compelled to say it anyway.
>
>The fact that there is no record of a test
>being made and having a positive result
>does not prove that there was a test and
>the result was negative. Saying that it's
>so is, in fact, somewhat illogical.
>
>The truism is "absence of evidence is not
>evidence of absence." Let's fill this in
>-- Absence of evidence that crazed ware is
>unsafe is not evidence that crazed ware
>is safe. The inverse is likewise true --
>Absence of evidence that crazed ware is
>safe is not evidence that crazed ware is
>unsafe.
>
>In the absence of evidence that the safety
>of crazed ware has ever been tested, it is
>not possible to conclude that crazed ware
>has been tested and proved safe.
>
>We can apply what we do know to probability
>of risk. We do know that it's somewhat
>harder to clean crazed ware -- that's why
>heavily crazed ware retains the aromas of foods
>when uncrazed ware does not.
>
>We also know that very high temperature
>cleaning (steam especially) will eliminate
>these aromas in many cases. Clearly, this
>indicates that whatever risks to remain
>are somewhat attenuated by very high temperature
>cleaning. The probability of risk with
>crazed ware can be reduced with more
>careful cleaning.
>
>Has crazed ware been used for hundreds
>-- even thousands -- of years? Yes!
>And in most of those years, people got
>sick from food-related illnesses regularly
>and died young. Can we 'prove' that this
>was related to crazed ware? No.
>
>But put a nice bit of smoked halibut
>on two plates, one visibly crazed, one
>not, and leave them to sit for a few
>hours. Come lunch time, consume the
>halibut. (Not a required part of the
>test, but the best part.) Wash both
>in the same fashion, detergent, water
>(not to hot to wash by hand), and dry
>(use different towels for each).
>
>Sniff them both. Do they smell
>different? If they do, you've
>established that using your processes,
>there is a difference between the two.
>(The test can be made better by having
>a disinterested party, unaware of the
>nature of the test or the difference
>between the two plates, do the sniff
>test. Better still to have a third
>disinterested party do the washing,
>likewise unaware of the issues.)
>
>For myself, I am always very
>concerned with a presumption made
>on the basis of the theory that
>"they" must have already checked
>it and found it safe. If there's
>anything we learn from perusing the
>daily news, it's that "they" are a
>lot dumber than they look, and
>rarely investigate anything until
>after there's an outbreak of trouble.
>
>Climbing down from the soapbox --
>
>Steve Slatin
>
>
>
>
>--- On Thu, 7/10/08, Ivor and Olive Lewis wrote:
>
>> > Dear Vince,
>> I do not have access to the archives of those companies or
>> institutions that may have done this research.
>> Frank Hamer is silent on the matter. So are Felix and Sonya
>> Singer.
>> Hence, your opinion <<... if there was even the
>> slightest danger of
>> craze cracks
>> harbouring dangerous bacteria we would all know about it.
>> ...>> seems
>> to be upheld, since nothing is said about the possibility
>> of such a
>> hazard in either text.
>> Best regards,
>> Ivor Lewis
Ron Roy
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Kenneth Chin-Purcell on wed 16 jul 08
On Jul 16, 2008, at 4:16 PM, Ron Roy wrote:
> Why do so many potters think that crazed ware is nothing to complain
> about?
I know this question is partly rhetorical, but I think about this a
bit. I'm "that potter" who actually cares about this issue, and since
I make pots for use with food I sell only non-crazed ware. One of the
big reasons I do this is for durability, but I also like that it is
more sanitary. Mostly I want to send someone home with a pot that
won't chip and still rings true after years of use.
I have to admit though that I'm a bit shy about the issue. With
customers I think it comes off as a bit too technical to push the
"durable and safe" angle. Most of my customers want an artistic
experience; they are looking for something beautiful and expressive -
talking about sanitation is a bit of a buzz kill. If they ask about
using a dishwasher I may get into it.
Worse is what happened yesterday - customer was talking about a new
dinnerware set, because her old set of twelve have *all* cracked
except for three salad plates. This set is about seven years old and
was thrown by a well known talented local potter - a much better known
potter than myself. So then it's my task to somehow point out that my
plates would still ring true without diss'ing the well known potter.
So to get back to Ron's question, I think the answer is:
1) Customers assume a low level of utility - they assume that handmade
ware needs to be hand washed, will chip, etc. They have heard about
lead, but that's about it.
2) Most potters don't care, so the force of the crowd is with them.
Having made the effort though, I would be uncomfortable selling
someone a crazed pot for food use.
-- Ken Chin-Purcell
Bungalow Pottery
Taylor Hendrix on wed 16 jul 08
Dear Stevie Wounder,
Um, how concerned are you that your
equation persistent odor=bacterial
contamination=bad? I have a gallon
pickle jar (glass) that still smells like
pickles. Okay, there are still about
10 pickles in there but I KNOW it is
going to smell like pickles once I wash
it out, so there. Anyone else give up
saving the salsa bottles for glaze
ingredients because the stinky was
still there? Don't even get me started
on some of our plastic containers.
Humans, though not nearly as capable
(oh, in so many things) as dogs,
can detect some odors resulting
in concentrations that are low indeed.
Furthermore, odor is transmitted by
molecules which are much, much smaller
in size than even the smallest of disease
causing bacteria. How does your example
correlate?
Yes, I am being argumentative. Yes, I do
feel that crazing can be an issue. Yes, I
am interested in knowing if harmful
bacteria can harbor in crazed glazes even
through a light washing. And No, I do not
believe that the argument "we haven't had
a problem in 5000 years, so there must
not be one" is a sound one either.
I'm bored,
Taylor, in Rockport TX
On Fri, Jul 11, 2008 at 10:41 AM, Steve Slatin wrote:
> Ivor -- Vince --
>
> I know this can be taken as argumentative,
> but I find myself compelled to say it anyway.
...
> We can apply what we do know to probability
> of risk. We do know that it's somewhat
> harder to clean crazed ware -- that's why
> heavily crazed ware retains the aromas of foods
> when uncrazed ware does not.
...
Sam Kelly on thu 17 jul 08
Im pretty sure no one has been diognosed as "death caused by crazed =20
breakfeast bowl".
Quoting Ron Roy :
> I must say I think Steve has made some very important points here.
>
> Why do so many potters think that crazed ware is nothing to complain about=
?
> Surely there are obvious and compelling reasons that uncrazed ware is
> superior - for many reasons.
>
> Why are there government rules about this for restaurants?
>
> Are we - as a group - simply not capable of solving the problem or just no=
t
> interested?
>
> RR
>
>
>> I know this can be taken as argumentative,
>> but I find myself compelled to say it anyway.
>>
>> The fact that there is no record of a test
>> being made and having a positive result
>> does not prove that there was a test and
>> the result was negative. Saying that it's
>> so is, in fact, somewhat illogical.
>>
>> The truism is "absence of evidence is not
>> evidence of absence." Let's fill this in
>> -- Absence of evidence that crazed ware is
>> unsafe is not evidence that crazed ware
>> is safe. The inverse is likewise true --
>> Absence of evidence that crazed ware is
>> safe is not evidence that crazed ware is
>> unsafe.
>>
>> In the absence of evidence that the safety
>> of crazed ware has ever been tested, it is
>> not possible to conclude that crazed ware
>> has been tested and proved safe.
>>
>> We can apply what we do know to probability
>> of risk. We do know that it's somewhat
>> harder to clean crazed ware -- that's why
>> heavily crazed ware retains the aromas of foods
>> when uncrazed ware does not.
>>
>> We also know that very high temperature
>> cleaning (steam especially) will eliminate
>> these aromas in many cases. Clearly, this
>> indicates that whatever risks to remain
>> are somewhat attenuated by very high temperature
>> cleaning. The probability of risk with
>> crazed ware can be reduced with more
>> careful cleaning.
>>
>> Has crazed ware been used for hundreds
>> -- even thousands -- of years? Yes!
>> And in most of those years, people got
>> sick from food-related illnesses regularly
>> and died young. Can we 'prove' that this
>> was related to crazed ware? No.
>>
>> But put a nice bit of smoked halibut
>> on two plates, one visibly crazed, one
>> not, and leave them to sit for a few
>> hours. Come lunch time, consume the
>> halibut. (Not a required part of the
>> test, but the best part.) Wash both
>> in the same fashion, detergent, water
>> (not to hot to wash by hand), and dry
>> (use different towels for each).
>>
>> Sniff them both. Do they smell
>> different? If they do, you've
>> established that using your processes,
>> there is a difference between the two.
>> (The test can be made better by having
>> a disinterested party, unaware of the
>> nature of the test or the difference
>> between the two plates, do the sniff
>> test. Better still to have a third
>> disinterested party do the washing,
>> likewise unaware of the issues.)
>>
>> For myself, I am always very
>> concerned with a presumption made
>> on the basis of the theory that
>> "they" must have already checked
>> it and found it safe. If there's
>> anything we learn from perusing the
>> daily news, it's that "they" are a
>> lot dumber than they look, and
>> rarely investigate anything until
>> after there's an outbreak of trouble.
>>
>> Climbing down from the soapbox --
>>
>> Steve Slatin
>>
>>
>>
>>
>> --- On Thu, 7/10/08, Ivor and Olive Lewis wrote:
>>
>>> > Dear Vince,
>>> I do not have access to the archives of those companies or
>>> institutions that may have done this research.
>>> Frank Hamer is silent on the matter. So are Felix and Sonya
>>> Singer.
>>> Hence, your opinion <<... if there was even the
>>> slightest danger of
>>> craze cracks
>>> harbouring dangerous bacteria we would all know about it.
>>> ...>> seems
>>> to be upheld, since nothing is said about the possibility
>>> of such a
>>> hazard in either text.
>>> Best regards,
>>> Ivor Lewis
>
> Ron Roy
> 15084 Little Lake Road
> Brighton, Ontario
> Canada
> K0K 1H0
>
Lee Love on thu 17 jul 08
On Wed, Jul 16, 2008 at 5:40 PM, Taylor Hendrix wrote:
>a problem in 5000 years, so there must
>not be one" is a sound one either.
A lack of respect for traditional knowledge is endemic in our society.
> I'm bored,
I have come to the conclusion that it must either be too much time
on one's hands, or the need to sell books. ;^)
I have been unable to be bored since about junior high.
--
Lee Love in Minneapolis
http://mashikopots.blogspot.com/
http://claycraft.blogspot.com/
"Let the beauty we love be what we do.
There are hundreds of ways to kneel and kiss the ground." --Rumi
Bill Merrill on thu 17 jul 08
Rhodes #32 glaze is also known as Mamo after a student from Alfred used
it considerably with 5% tin oxide. The glaze goes back to the days of
Harder and Binns. Many potters have used that glaze. It is a most
beautiful matt glaze. I use it with 5% Zirox 100 (a direct substitute
for Opax) plus an additional 5% Dolomite. It is the best, I believe at
cone 9 1/2 over a light iron stoneware body. The reason I am writing
this is with regards to a question of crazing. The glaze because it is
a high clay matt scuffs if a fork or knife is run across a surface of a
plate. If one is not cutting on it is a most beautiful glaze. If you
look up the following site on Flikr there are a few of my pots. The
pitcher has a versions of #32 on it, used thick and thin. The vase(last
picture) is #32 on the top and a red matt on the bottom of the vase.
=20
http://www.flickr.com/photos/25594880@N04/
=20
I would not use this in a casserole, but for other uses it is a very
stable glaze. Matt glazes can craze and you may not see the crazing
until the pot is used and the crazing has stained the glaze.=20
=20
=20
=20
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Kenneth
Chin-Purcell
Sent: Thursday, July 17, 2008 9:30 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: Crazing Hazards. Verification ?
=20
Hi Lee,
=20
Well, as usual, it's hard to convey the tone I wanted via email. I
think we're more on the same page than perhaps I came across.
=20
I agree that silk kimonos don't go in the wash, and that's the way it
should be. I was just trying to answer Ron's question honestly. I
think most pottery customers are not looking for bomb proof pots -
they are shopping on more aesthetic qualities. And I think implicit
in that is that most pottery customers expect to hand wash hand made
pots and treat them as more fragile than commercial ware. Crazing
isn't really an issue at the point of sale, in my experience. If it
was then I think potters would respond.
=20
And I never meant that most potters are lazy or lack the knowledge -
please don't conflate my words with others. But I would stand by the
assertion that most potter's priorities are elsewhere, and that there
is a certain comfort in taking the side of tradition and common
practice.
=20
Really, I'm not advocating banning Rhodes 32. Ron asked a question
and I thought I would give a try at answering it. I also thought that
other potters would be interested in my stance, that from *my*
perspective I've decided to not sell crazed ware (matte or glossy).
It's become part of how I approach ceramics. It's still a big tent
though - I don't see a need for orthodoxy on this issue.
=20
-- Ken C-P
=20
=20
On Jul 17, 2008, at 9:36 AM, Lee Love wrote:
=20
> On Wed, Jul 16, 2008 at 9:38 PM, Kenneth Chin-Purcell
> wrote:
>=20
>> 1) Customers assume a low level of utility - they assume that
>> handmade
>> ware needs to be hand washed, will chip, etc. They have heard about
>> lead, but that's about it.
>=20
> Not all craft is wash and wear. Most of the world understands you
> can't put a silk kimono in the washing machine.
>=20
> Primarily, this is important to keep in mind, so as not to
> "chicken little" people away from traditional highfired pottery that
> you find in the antique stores.
>=20
>=20
>> 2) Most potters don't care, so the force of the crowd is with them.
>=20
> It is fine to raise questions of crazing related to craftmanship.
> But blanket statements that "most potters don't care" or "they are too
> lazy" or "don't know how" is simply baseless and condescending.
>=20
> That tone, along with frightening folks away from traditional
> wares and earthenware really does a disservice to the diversity of our
> craft.
>=20
>=20
>> Having made the effort though, I would be uncomfortable selling
>> someone a crazed pot for food use.
>=20
> the most typical way folks avoid crazing is with mat glazes. As we
> know, there are good and bad mat glazes.
>=20
> Another way, is not to glaze at all as in traditional unglazed
> wood fire. This works fine on vitreous ware.
>=20
> --
> Lee Love in Minneapolis
> http://mashikopots.blogspot.com/
> http://claycraft.blogspot.com/
>=20
> "Let the beauty we love be what we do.
> There are hundreds of ways to kneel and kiss the ground." --Rumi
Lee Love on thu 17 jul 08
On Thu, Jul 17, 2008 at 11:29 AM, Kenneth Chin-Purcell
wrote:
> And I never meant that most potters are lazy or lack the knowledge -
> please don't conflate my words with others.
Those are Ron's words. I have no quibble with folks desiring to make
glazes that don't craze.
> Really, I'm not advocating banning Rhodes 32.
Especially not Mel's, with extra silica.
--
Lee Love in Minneapolis
http://mashikopots.blogspot.com/
http://claycraft.blogspot.com/
"Let the beauty we love be what we do.
There are hundreds of ways to kneel and kiss the ground." --Rumi
Lee Love on thu 17 jul 08
On Wed, Jul 16, 2008 at 9:38 PM, Kenneth Chin-Purcell
wrote:
> 1) Customers assume a low level of utility - they assume that handmade
> ware needs to be hand washed, will chip, etc. They have heard about
> lead, but that's about it.
Not all craft is wash and wear. Most of the world understands you
can't put a silk kimono in the washing machine.
Primarily, this is important to keep in mind, so as not to
"chicken little" people away from traditional highfired pottery that
you find in the antique stores.
> 2) Most potters don't care, so the force of the crowd is with them.
It is fine to raise questions of crazing related to craftmanship.
But blanket statements that "most potters don't care" or "they are too
lazy" or "don't know how" is simply baseless and condescending.
That tone, along with frightening folks away from traditional
wares and earthenware really does a disservice to the diversity of our
craft.
> Having made the effort though, I would be uncomfortable selling
> someone a crazed pot for food use.
the most typical way folks avoid crazing is with mat glazes. As we
know, there are good and bad mat glazes.
Another way, is not to glaze at all as in traditional unglazed
wood fire. This works fine on vitreous ware.
--
Lee Love in Minneapolis
http://mashikopots.blogspot.com/
http://claycraft.blogspot.com/
"Let the beauty we love be what we do.
There are hundreds of ways to kneel and kiss the ground." --Rumi
Kenneth Chin-Purcell on thu 17 jul 08
Hi Lee,
Well, as usual, it's hard to convey the tone I wanted via email. I
think we're more on the same page than perhaps I came across.
I agree that silk kimonos don't go in the wash, and that's the way it
should be. I was just trying to answer Ron's question honestly. I
think most pottery customers are not looking for bomb proof pots -
they are shopping on more aesthetic qualities. And I think implicit
in that is that most pottery customers expect to hand wash hand made
pots and treat them as more fragile than commercial ware. Crazing
isn't really an issue at the point of sale, in my experience. If it
was then I think potters would respond.
And I never meant that most potters are lazy or lack the knowledge -
please don't conflate my words with others. But I would stand by the
assertion that most potter's priorities are elsewhere, and that there
is a certain comfort in taking the side of tradition and common
practice.
Really, I'm not advocating banning Rhodes 32. Ron asked a question
and I thought I would give a try at answering it. I also thought that
other potters would be interested in my stance, that from *my*
perspective I've decided to not sell crazed ware (matte or glossy).
It's become part of how I approach ceramics. It's still a big tent
though - I don't see a need for orthodoxy on this issue.
-- Ken C-P
On Jul 17, 2008, at 9:36 AM, Lee Love wrote:
> On Wed, Jul 16, 2008 at 9:38 PM, Kenneth Chin-Purcell
> wrote:
>
>> 1) Customers assume a low level of utility - they assume that
>> handmade
>> ware needs to be hand washed, will chip, etc. They have heard about
>> lead, but that's about it.
>
> Not all craft is wash and wear. Most of the world understands you
> can't put a silk kimono in the washing machine.
>
> Primarily, this is important to keep in mind, so as not to
> "chicken little" people away from traditional highfired pottery that
> you find in the antique stores.
>
>
>> 2) Most potters don't care, so the force of the crowd is with them.
>
> It is fine to raise questions of crazing related to craftmanship.
> But blanket statements that "most potters don't care" or "they are too
> lazy" or "don't know how" is simply baseless and condescending.
>
> That tone, along with frightening folks away from traditional
> wares and earthenware really does a disservice to the diversity of our
> craft.
>
>
>> Having made the effort though, I would be uncomfortable selling
>> someone a crazed pot for food use.
>
> the most typical way folks avoid crazing is with mat glazes. As we
> know, there are good and bad mat glazes.
>
> Another way, is not to glaze at all as in traditional unglazed
> wood fire. This works fine on vitreous ware.
>
> --
> Lee Love in Minneapolis
> http://mashikopots.blogspot.com/
> http://claycraft.blogspot.com/
>
> "Let the beauty we love be what we do.
> There are hundreds of ways to kneel and kiss the ground." --Rumi
Kim Hohlmayer on fri 18 jul 08
Hi Ken,
I love words. I have never seen the word "conflate." I get the gist but I will need to go hame and look that one up in my Funk and Wagnell. --Kim H.
Kim Hohlmayer on fri 18 jul 08
Yes, not all work is meant to be roughly handled in the everyday world. My favorite post card shows a photo of a Navaho or Hopi woman sitting with her pottery out around her. It was probably taken at a Southwest train station at the turn of the last century when Native Americans came and set up to sell their fine craft work to the tourists. The caption reads: "Yeah, sure lady, they're oven proof microwave and dishwasher safe."
I believe in fine craftmanship and that if I make something for kitchen/dining room use it should be durable. However, as long as we keep our buying public informed as to what can and can't be done with our ware the choice to buy is theirs. The exception is safety. Buying a fine china cup with gold edges that must be had washed or a stoneware mug I can wash any way I wish is a personal choice. Not knowing that a crazed glaze could be leaching unsafe chemicals into my food even in small amounts is a whole separate subject which I think we have covered in depth over the past several weeks. --Kim H.
--- On Thu, 7/17/08, Lee Love wrote:
> From: Lee Love
> Subject: Re: Crazing Hazards. Verification ?
> To: CLAYART@LSV.CERAMICS.ORG
> Date: Thursday, July 17, 2008, 10:36 AM
> On Wed, Jul 16, 2008 at 9:38 PM, Kenneth Chin-Purcell
> wrote:
>
> > 1) Customers assume a low level of utility - they
> assume that handmade
> > ware needs to be hand washed, will chip, etc. They
> have heard about
> > lead, but that's about it.
>
> Not all craft is wash and wear. Most of the world
> understands you
> can't put a silk kimono in the washing machine.
>
> Primarily, this is important to keep in mind, so as not
> to
> "chicken little" people away from traditional
> highfired pottery that
> you find in the antique stores.
>
>
> > 2) Most potters don't care, so the force of the
> crowd is with them.
>
> It is fine to raise questions of crazing related to
> craftmanship.
> But blanket statements that "most potters don't
> care" or "they are too
> lazy" or "don't know how" is simply
> baseless and condescending.
>
> That tone, along with frightening folks away from
> traditional
> wares and earthenware really does a disservice to the
> diversity of our
> craft.
>
>
> > Having made the effort though, I would be
> uncomfortable selling
> > someone a crazed pot for food use.
>
> the most typical way folks avoid crazing is with mat
> glazes. As we
> know, there are good and bad mat glazes.
>
> Another way, is not to glaze at all as in
> traditional unglazed
> wood fire. This works fine on vitreous ware.
>
> --
> Lee Love in Minneapolis
> http://mashikopots.blogspot.com/
> http://claycraft.blogspot.com/
>
> "Let the beauty we love be what we do.
> There are hundreds of ways to kneel and kiss the
> ground." --Rumi
Ron Roy on sun 20 jul 08
Well - most people will assume that all pottery can be used in the
microwave oven and that is a fact.
If potters are going to make semi functional ware it is up to them to warn
the customer what it is not good for.
We are talking about people trying to make a living making hand made
functional ware - especially those who are trying to do it in a responsible
way. They deserve our support and our admiration.
RR
> Not all craft is wash and wear. Most of the world understands you
>can't put a silk kimono in the washing machine.
Ron Roy
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Ivor and Olive Lewis on tue 22 jul 08
Dear May Luc,
Regarding the quality comparison and the results of your straw poll.
Some years ago I attended a workshop and we were discussing a similar
line of inquiry.
One of the attendees made the following point about coffee mugs. He
told us "We test all of ours and if they do not survive they go to
land fill". We were curious about his testing method. "Just push them
of the bench . If they hit the concrete and bounce they go on the
shelves.".
Well designed and attractively decorated pots will always sell if the
price is right for the buyer.
You may have to adopt the "Loss Leader" approach to your family
members and salt the market with a few well placed samples.
Sincere regards,
Ivor
Lee Love on tue 22 jul 08
Ron,
It seems like non-high fire glossy has the most problems. You
avoid much of the temperamental nature of cone 6 at higher temps.
--
Lee Love in Minneapolis
http://mashikopots.blogspot.com/
http://claycraft.blogspot.com/
"Let the beauty we love be what we do.
There are hundreds of ways to kneel and kiss the ground." --Rumi
Lee Love on tue 22 jul 08
On Tue, Jul 22, 2008 at 11:13 PM, Ron Roy wrote:
> I do think that many potters don't know how to deal with crazing glazes
> which would be one explanation why there are so many crazed pots around and
> why so many potters are happy to put up with it.
Ron,
There is nothing "mystical" about it. But folks use it as a
marketing tool to sell books.
--
Lee Love in Minneapolis
http://mashikopots.blogspot.com/
http://claycraft.blogspot.com/
"Let the beauty we love be what we do.
There are hundreds of ways to kneel and kiss the ground." --Rumi
May Luk on tue 22 jul 08
The problem is most non-potting citizens think that craft is all silk kimon=
o - it's inaccessible.
I recently did an unscientific survey with my family; my uncles, cousins an=
d my brother. Unlike me, they all own homes and have steady incomes, upscal=
e kitchen appliances and granite counter tops. I asked them why they don't =
use hand made ceramics. The consensus is that it's expensive and it's fragi=
le. They don't want to bother. My brother uses the ugliest mugs from Walmar=
t because they are dishwasher safe. They must have little extra money to sp=
end on some nice hand made pottery. How can I reach into their wallets for =
my potter friends who try to make a living making functional wares?
Regards
May
Kings County, NY
I mind crazed glaze on my mug. Also, if it looks like a mistake.=20
[...]
> We are talking about people trying to make a living making
> hand made
> functional ware - especially those who are trying to do it
> in a responsible
> way. They deserve our support and our admiration.
>=20
> RR
>=20
>=20
> > Not all craft is wash and wear. Most of the world
> understands you
> >can't put a silk kimono in the washing machine.
>
=0A=0A=0A __________________________________________________________=
=0ANot happy with your email address?.=0AGet the one you really want - mill=
ions of new email addresses available now at Yahoo! http://uk.docs.yahoo.co=
m/ymail/new.html
Ron Roy on wed 23 jul 08
Thanks Ken,
This helps me understand the problem better - your attitude is refreshing
and you are not alone - there are more potters than ever trying to do the
best possible job of providing well crafted ware.
When I visit potters web sites I see it more and more - dishwasher and
microwave safe.
Can you give me some idea of how you solve the crazing problem?
RR
>On Jul 16, 2008, at 4:16 PM, Ron Roy wrote:
>
>> Why do so many potters think that crazed ware is nothing to complain
>> about?
>
>I know this question is partly rhetorical, but I think about this a
>bit. I'm "that potter" who actually cares about this issue, and since
>I make pots for use with food I sell only non-crazed ware. One of the
>big reasons I do this is for durability, but I also like that it is
>more sanitary. Mostly I want to send someone home with a pot that
>won't chip and still rings true after years of use.
>
>I have to admit though that I'm a bit shy about the issue. With
>customers I think it comes off as a bit too technical to push the
>"durable and safe" angle. Most of my customers want an artistic
>experience; they are looking for something beautiful and expressive -
>talking about sanitation is a bit of a buzz kill. If they ask about
>using a dishwasher I may get into it.
>
>Worse is what happened yesterday - customer was talking about a new
>dinnerware set, because her old set of twelve have *all* cracked
>except for three salad plates. This set is about seven years old and
>was thrown by a well known talented local potter - a much better known
>potter than myself. So then it's my task to somehow point out that my
>plates would still ring true without diss'ing the well known potter.
>
>So to get back to Ron's question, I think the answer is:
>
>1) Customers assume a low level of utility - they assume that handmade
>ware needs to be hand washed, will chip, etc. They have heard about
>lead, but that's about it.
>
>2) Most potters don't care, so the force of the crowd is with them.
>
>Having made the effort though, I would be uncomfortable selling
>someone a crazed pot for food use.
>
>-- Ken Chin-Purcell
>Bungalow Pottery
Ron Roy
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Ron Roy on wed 23 jul 08
Lee - I don't understand this - how is it possible to avoid crazing by
using mat glazes?
>the most typical way folks avoid crazing is with mat glazes. As we
>know, there are good and bad mat glazes.
> Lee Love in Minneapolis
Ron Roy
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Ron Roy on wed 23 jul 08
Wrong again Lee,
I don't think potters are lazy - seems to me you can't be a potter and be lazy.
I do think that many potters don't know how to deal with crazing glazes
which would be one explanation why there are so many crazed pots around and
why so many potters are happy to put up with it.
RR
>> And I never meant that most potters are lazy or lack the knowledge -
>> please don't conflate my words with others.
>
>Those are Ron's words. I have no quibble with folks desiring to make
>glazes that don't craze.
Ron Roy
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Ivor and Olive Lewis on thu 24 jul 08
As far as I can see, using a matt glaze would conceal this defect, not
eliminate it.
It is a pity clay workers do not have access to the technology of the
Metallurgist. They have a Dye Disclosure Test that is universally
accepted as well as X-ray and Sonic methods for detecting internal
flaws.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
L TURNER on thu 24 jul 08
Ivor,
Have you any data on the ring test for glazed and crazed pieces? When a
piece comes from the kiln, I thump it with my finger to see how it rings.
If it doesn't, I look harder to find the crack. I don't usually keep crazed
pieces unless it can serve as sculpture and the crazes add to the aesthetic
value so I don't have anything with crazes to test to see if it rings.
L. Turner
Lee Love on thu 24 jul 08
On Thu, Jul 24, 2008 at 1:17 AM, Ivor and Olive Lewis
wrote:
> As far as I can see, using a matt glaze would conceal this defect, not
> eliminate it.
That was my point Ivor.
--
Lee Love in Minneapolis
http://mashikopots.blogspot.com/
http://claycraft.blogspot.com/
"Let the beauty we love be what we do.
There are hundreds of ways to kneel and kiss the ground." --Rumi
Steve Slatin on fri 25 jul 08
Taylor -- (Now am I supposed to call you TayTay the
Phlox or what?)
The equation is different than that, and expressed
in possibilities, not certainties. It's "persistent
odor demonstrates that something remains, something
may be (and I emphasize that 'may') a source of bacterial
infection, and some bacterial infections
are bad.
My point, though, is a narrower one -- it
is that it is not possible to rationally
conclude that there is no risk based solely
on the fact that you have never heard tell
of the existence of the risk.
200 years ago, no one knew of the existence
of risk from germs -- in facts, the germ
theory of infection hadn't been completely
enunciated. No one really knew why women
died from pleupural fever, so the actual
existence of the risk was invisible -- all
people knew was that pregnant women died
in large numbers shortly after delivery.
I can remember when shoe stores
featured fluoroscopes so you could see your
foot wiggle in the outline of the shoe -- and
no one knew of the existence of the risk of
limitless exposure to x-rays. (And I'm not
actually all that old.) None of the shoe
salesmen knew of the risk, and it was a great
selling tool "See how well the little guy's
feet fit in those shoes!") Their not having
heard of the risk had nothing to do with
the fact that there was a risk.
Not only does it sometimes occur that we
find that something that's touted to be
unsafe turns out not to be, it sometimes
occurs that something touted to be safe
turns out not to be.
But to believe that something must be safe
because you personally haven't heard that
it is not? It doesn't stand up unless
"they" have done reliable experiments
on everything, and only told you about
the experiments that showed risk.
The fact that you don't know of such
experiments doesn't logically lead to
the conclusion that the experiments
did exist -- actually, it tends to
the opposite conclusion -- and the
outcome was negative.
Some people here really trust "them"
to do all of the requisite testing.
The people no doubt believe that Fen-Phen
is safe, and Vioxx, and Baycol, and
Thalidomide is just the very best
thing to take to quell morning sickness
in young pregnant women.
Now I'm not saying there must be a
serious level of risk to crazed
functional ware. I'm saying that
if you test, and your tests are
negative, you've diminished the
probability of risk to the level
of your testing.
(The demonstration
of a negative is always a difficult
matter -- I recollect that the
earliest published citation of
Einstein's theory was by a guy
who purported to 'prove' that it
was wrong, because he'd done an
experiment that didn't show the
result that Einstein anticipated.
If his experiment had been more
refined, he might have confirmed
special relativity. Instead,
he concluded that Einstein was
wrong. Consequently, though
this guy (Kaufman or Kauffman,
and he was a great experimentalist
and deserves great honor) he is
remembered primarily as the first
boob to believe that he had
successfully 'disproved Einstein.')
Now as to the pickle jars, something
else I'd point out is that the pickle
smell is an organic aroma -- as is the
peanut smell, etc. -- and organics
very rarely survive heating at over
1000 F. Most live bacteria kick the
bucket by 212 F, and the things that
persist are exotic, like the bacteria
that live at underwater volcanoes and
prions and so on.
So firing the stuff almost certainly
renders it safe (hence my lack of
concern with the use of bone ash as
a glaze ingredient, even though some
zoonotic diseases may be transmissible
through bone consumption). Use your
pickle jars with impunity, man!
Steve Slatin --
--- On Wed, 7/16/08, Taylor Hendrix wrote:
> Dear Stevie Wounder,
>
> Um, how concerned are you that your
> equation persistent odor=bacterial
> contamination=bad? I have a gallon
> pickle jar (glass) that still smells like
> pickles. Okay, there are still about
> 10 pickles in there but I KNOW it is
> going to smell like pickles once I wash
> it out, so there. Anyone else give up
> saving the salsa bottles for glaze
> ingredients because the stinky was
> still there? Don't even get me started
> on some of our plastic containers.
>
> Humans, though not nearly as capable
> (oh, in so many things) as dogs,
> can detect some odors resulting
> in concentrations that are low indeed.
> Furthermore, odor is transmitted by
> molecules which are much, much smaller
> in size than even the smallest of disease
> causing bacteria. How does your example
> correlate?
>
> Yes, I am being argumentative. Yes, I do
> feel that crazing can be an issue. Yes, I
> am interested in knowing if harmful
> bacteria can harbor in crazed glazes even
> through a light washing. And No, I do not
> believe that the argument "we haven't had
> a problem in 5000 years, so there must
> not be one" is a sound one either.
>
> I'm bored,
>
> Taylor, in Rockport TX
Vince Pitelka on sat 26 jul 08
Steve Slatin wrote:
> The equation is different than that, and expressed
> in possibilities, not certainties. It's "persistent
> odor demonstrates that something remains, something
> may be (and I emphasize that 'may') a source of bacterial
> infection, and some bacterial infections
> are bad. My point, though, is a narrower one -- it
> is that it is not possible to rationally
> conclude that there is no risk based solely
> on the fact that you have never heard tell
> of the existence of the risk.
AAAARRRRRGGGGHHHHH! (To quote Charlie Brown). To repeat, once more, (and
forgive me for writing in capital letters, because I know they indicate
that the writer is yelling. In this case, I AM YELLING!) THERE IS
ABSOLUTELY NO DEMONSTRABLE PROOF OR EVEN THE SLIGHTEST INDICATION THAT
THERE IS ANY RISK WHATSOEVER OF ILLNESS OR POISONING RESULTING FROM CRAZE=
D
GLAZES. NO ONE HAS EVER PUBLISHED THE SLIGHTEST WARNING OF ANY DANGER,
AND LACKING THAT OVER THE PAST FEW CENTURIES, THE ONLY REASONABLE
CONCLUSION IS TO AGREE THAT THERE SIMPLY IS ABSOLUTELY NO DANGER FROM
CRAZED GLAZES.
At this point, I cannot imagine any reason why someone would continue to
post warnings about crazed glazes, except for the acknowledged concern
that an unstable glaze inclined to release toxic substances might do so
more quickly through craze cracks, although even that is unproven. Also,
it has been understood throughout this conversation that a crazed glaze
makes the fired product slightly weaker structurally.
Otherwise, could we please stop wasting time on imaginary risks? There
are way too many REAL risks in the world to engage in such a fool's
mission.
- Vince
Vince Pitelka
Appalachian Center for Craft
Tennessee Technological University
vpitelka@dtccom.net
http://iweb.tntech.edu/wpitelka/
Neon-Cat on sun 27 jul 08
Dear Vince (I write in a sweet, soft lowercase email "voice"),
Just because no one in our field has published an article on the dangers of
crazed ceramic glazes that can be referenced by one of us does not mean that
an article does not exist. I am finding it hard to believe such an article
has not already been written. Researchers in many diversified fields have
looked into the crazing of ceramics and found crazing to be undesirable -
from meat packing plants, to dental offices, restaurants, nuclear waste
containment projects, within the medical field with its implants and
devices, environmental encapsulation, cleaning and disinfection industries
and concerns, the electronics field, etc. Perhaps it is a kindness that such
an article does not exist - much of the world uses crazed dinner- and
cookware. Why frighten them? That germs can and do colonize more easily in
crazed material has long been proven. That objects are harder to clean and
disinfect if they are crazed has also been proven over and over again. That
some microbe colonies can never be completely eradicated no matter what
standard cleaning agent is employed has also been proven. To write an
article on the dangers of crazed glaze for publication within the ceramic
field would be a time-consuming undertaking and one guaranteed not to win
friends among one's fellow potters. Lose-lose. One could have a bounty on
one's head for years to come as such an article cycled endlessly through
cyber-space.
If I were making dinnerware and cookware though I'd want to send it our
craze-free. But that's me. "Primitive" man was capable of making craze-free
ware so why can't more modern men and women? Why not offer the world the
best in art and functionality? Crazing is not a problem for what I do but
tell me, is it so hard for potters to achieve a craze-free glaze?
I am not starving this week so prefer to eat off paper plates or uncrazed
plates. Were my options starvation or food on a crazed plate I'd still opt
for food on a crazed plate and take a chance that all would be well -- the
odds would be in my favor.
And yes, I'm still here, perfectly well, to tell you that I recently ate
food, some served on crazed platters, gleefully and with total abandon. It
was lovingly prepared by fellow students for lunches at school. A real
godsend at the time.
And no, I won't be writing that definitive article on the dangers of crazed
glazes - potters seem like a nice group of people, intelligent and
thoughtful, and I'm just making friends. What I will do, if given the right
moment and opportunity, is to mention enthusiastically any nice-looking
glaze that will not craze for its given range and firing conditions using
proper glazing techniques and application methods.
Marian
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG]On Behalf Of Vince Pitelka
Sent: Saturday, July 26, 2008 9:44 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: Crazing Hazards. Verification ?
(snip)
AAAARRRRRGGGGHHHHH! (To quote Charlie Brown). To repeat, once more, (and
forgive me for writing in capital letters, because I know they indicate
that the writer is yelling. In this case, I AM YELLING!) THERE IS
ABSOLUTELY NO DEMONSTRABLE PROOF OR EVEN THE SLIGHTEST INDICATION THAT
THERE IS ANY RISK WHATSOEVER OF ILLNESS OR POISONING RESULTING FROM CRAZED
GLAZES. NO ONE HAS EVER PUBLISHED THE SLIGHTEST WARNING OF ANY DANGER,
AND LACKING THAT OVER THE PAST FEW CENTURIES, THE ONLY REASONABLE
CONCLUSION IS TO AGREE THAT THERE SIMPLY IS ABSOLUTELY NO DANGER FROM
CRAZED GLAZES.
At this point, I cannot imagine any reason why someone would continue to
post warnings about crazed glazes, except for the acknowledged concern
that an unstable glaze inclined to release toxic substances might do so
more quickly through craze cracks, although even that is unproven. Also,
it has been understood throughout this conversation that a crazed glaze
makes the fired product slightly weaker structurally.
Otherwise, could we please stop wasting time on imaginary risks? There
are way too many REAL risks in the world to engage in such a fool's
mission.
- Vince
Vince Pitelka
Appalachian Center for Craft
Tennessee Technological University
vpitelka@dtccom.net
http://iweb.tntech.edu/wpitelka/
David Berg on sun 27 jul 08
Vince is correct, there has never been
anything published in the peer reviewed
medical literature that suggests someone
getting sick from crazed pottery. And the
reason there are no publications, is because
it doesn't happen ... not just because it hasn't
been discovered yet. There are lots of
publications about food illnesses, but no link
to crazed pottery. People get food illnesses
from eating bad food, not from the plate or cup
itself.
Our bodies already harbor billions upon billions
of bacteria ... most innocuous. There are even a
few virulent ones that get into us almost every
day by various & sundry routes that our immune
systems mop up & we never even know it. The
important point to consider whether one will get
sick or not, is the size of the inoculum (dose) of
bacteria that one might receive from using a
crazed plate or mug. There are simply not
enough bacteria living in the craze cracks to
make most relatively healthy persons sick ...
and that is assuming that every single
bacterium in all the cracks is even harmful
in the first place.
You're more likely to get sick from the actual
food that is on the plate & not from the plate
itself. People usually only get food poisoning
after eating a very large amount of harmful
bacteria in spoiled or improperly prepared
food. It is the huge dose of bugs that
overcomes the immune system & makes
one sick.
David
David Berg
dberg2@comcast.net
http://bergstoneware.com/
On Jul 25, 2008, at 11:39 PM, Steve Slatin wrote:
> ...
> My point, though, is a narrower one -- it
> is that it is not possible to rationally
> conclude that there is no risk based solely
> on the fact that you have never heard tell
> of the existence of the risk.
>
> 200 years ago, no one knew of the existence
> of risk from germs -- in facts, the germ
> theory of infection hadn't been completely
> enunciated...
> ...
> Steve Slatin --
Karin Givon on sun 27 jul 08
I thought the ongoing ad inf thread was all to entertain us with a
large variety of absurd thoughts. In case you hadn't noticed, clayart
ABOUNDS with entertaining and even absurd thoughts! I Adore hearing
from Taylor, from Lee, and John! And now even Vince! Who quotes
Charlie Brown! You guys may be serious but I'm laughing my ___
off . And the rest is so sweet, and helpful.
I think we should canonize Mel, even if his beautiful pots are 98%
inaccessible to a bunch of us. ( You can tell they're beautiful just
from the rimd that show up on Visi for about 4 seconds)
Anyway, I Love You Vince! That was the penultimate answer. Now we'll
get to see who, besides the giggling woman, responds.
Karin Givon
DancingDragonPottery.net
On Jul 26, 2008, at 7:43 PM, Vince Pitelka wrote:
Steve Slatin wrote:
> The equation is different than that, and expressed
> in possibilities, not certainties. It's "persistent
> odor demonstrates that something remains, something
> may be (and I emphasize that 'may') a source of bacterial
> infection, and some bacterial infections
> are bad. My point, though, is a narrower one -- it
> is that it is not possible to rationally
> conclude that there is no risk based solely
> on the fact that you have never heard tell
> of the existence of the risk.
AAAARRRRRGGGGHHHHH! (To quote Charlie Brown). To repeat, once more,
(and
forgive me for writing in capital letters, because I know they indicate
that the writer is yelling. In this case, I AM YELLING!) THERE IS
ABSOLUTELY NO DEMONSTRABLE PROOF OR EVEN THE SLIGHTEST INDICATION THAT
THERE IS ANY RISK WHATSOEVER OF ILLNESS OR POISONING RESULTING FROM
CRAZED
GLAZES. NO ONE HAS EVER PUBLISHED THE SLIGHTEST WARNING OF ANY DANGER,
AND LACKING THAT OVER THE PAST FEW CENTURIES, THE ONLY REASONABLE
CONCLUSION IS TO AGREE THAT THERE SIMPLY IS ABSOLUTELY NO DANGER FROM
CRAZED GLAZES.
At this point, I cannot imagine any reason why someone would continue to
post warnings about crazed glazes, except for the acknowledged concern
that an unstable glaze inclined to release toxic substances might do so
more quickly through craze cracks, although even that is unproven.
Also,
it has been understood throughout this conversation that a crazed glaze
makes the fired product slightly weaker structurally.
Otherwise, could we please stop wasting time on imaginary risks? There
are way too many REAL risks in the world to engage in such a fool's
mission.
- Vince
Vince Pitelka
Appalachian Center for Craft
Tennessee Technological University
vpitelka@dtccom.net
http://iweb.tntech.edu/wpitelka/
Lee Love on sun 27 jul 08
On Sat, Jul 26, 2008 at 9:43 PM, Vince Pitelka wrote:
> AAAARRRRRGGGGHHHHH! <...>
> ABSOLUTELY NO DEMONSTRABLE PROOF OR EVEN THE SLIGHTEST INDICATION THAT
> THERE IS ANY RISK WHATSOEVER OF ILLNESS OR POISONING RESULTING FROM CRAZED
> GLAZES.
Vince, it is very difficult to discuss these issues when folks seem
to have some kind of fundamentalist perspective on them. I only
write in response, as I think you do, to help beginners explore glaze
issues independently.
Don't accept every thing the gurus tell you. THINK for yourself!
If folks want to fix crazing because it is a craftsmanship
issue, I applaud them. But please, don't be scared into it by
irrational fear of germs. Rational proof is the carrot. Fear is a
stick.
--
Lee Love in Minneapolis
http://mashikopots.blogspot.com/
http://claycraft.blogspot.com/
"Let the beauty we love be what we do.
There are hundreds of ways to kneel and kiss the ground." --Rumi
David Berg on sun 27 jul 08
Marian,
Nothing is published because there are no data to
support it. No one is going to publish a scientific
manuscript about something that MIGHT happen.
It takes data & facts that are independently verified.
And scientists don't choose to NOT publish something
out of kindness. They choose NOT to publish
something that is not supported & backed up by data.
Yes, it's true, bacteria can be harbored in the craze
cracks but there is not one shred of evidence that proves
that anyone has ever gotten sick from them. Think about
it. We don't live in a sterile environment ... except for
the Bubble Boy. Your dishwasher will not sterilize your
dishes. There can be trace amounts of bacteria left on
"clean" dishes right out of the dishwasher. The food
we eat everyday is not sterile. The air we breathe is
not sterile. So the take home lesson is this: we
inadvertently eat & breathe in lots of bacteria everyday
and don't get sick ... regardless of whether the plates
are crazed or not. Our immune systems have evolved
to take care of it.
However, try eating the picnic potato salad that has
been incubating all day long in the hot sun ... that
might make you sick from the shear bacterial load
you just ingested even if you ate it from a sterile plate.
Here's a free summertime picnic tip for all: If you
do feel inclined to eat that suspect potato salad,
... you know what I'm talking about ... it might even
look a little bubbly around the edges where the
bacteria are really starting to multiply! At
least dip from the center where it stays cold the
longest & bacteria will invade last.
David
David Berg
dberg2@comcast.net
http://bergstoneware.com/
On Jul 27, 2008, at 3:08 PM, Neon-Cat wrote:
> Marion wrote:
> Dear Vince (I write in a sweet, soft lowercase email "voice"),
>
> Just because no one in our field has published an article on the
> dangers of
> crazed ceramic glazes that can be referenced by one of us does not
> mean that
> an article does not exist.
> ... Perhaps it is a kindness that such
> an article does not exist - much of the world uses crazed dinner- and
> cookware. Why frighten them? That germs can and do colonize more
> easily in
> crazed material has long been proven. ...
> Marian
>
Taylor Hendrix on sun 27 jul 08
Dear Nobel-gas-Cat:
This subject is a minor obsession for me. Would you point me in the
right direction for finding copies of those articles from divers
fields regarding crazing and health. Not being a smart butt about
anything here except your name.
Taylor, in Rockport TX
On Sun, Jul 27, 2008 at 2:08 PM, Neon-Cat wrote:
> Dear Vince (I write in a sweet, soft lowercase email "voice"),
...
Researchers in many diversified fields have
> looked into the crazing of ceramics and found crazing to be undesirable -
> from meat packing plants, to dental offices, restaurants, nuclear waste
> containment projects, within the medical field with its implants and
> devices, environmental encapsulation, cleaning and disinfection industries
> and concerns, the electronics field, etc.
...
Taylor Hendrix on sun 27 jul 08
Oops I can't spell. Ain't that sweet. I gave Neon-Cat an award! Grr, I
hate chemestry.
Tay Tay in Rock Rock
On Sun, Jul 27, 2008 at 3:37 PM, Taylor Hendrix wrote:
> Dear Nobel-gas-Cat:
>
...
Lee Love on sun 27 jul 08
On Sun, Jul 27, 2008 at 2:08 PM, Neon-Cat wrote:
>
>
> If I were making dinnerware and cookware though I'd want to send it our
> craze-free. But that's me. "Primitive" man was capable of making craze-free
> ware so why can't more modern men and women?
You crack me up Marian! Are you being facetious? All "primitive"
ware is unglazed earthenware. Are you trying to say that unglazed
unvitrified earthenware is safer than a crazed glaze on vitrified
stoneware?
Why not offer the world the
> best in art and functionality? Crazing is not a problem for what I do but
> tell me, is it so hard for potters to achieve a craze-free glaze?
Making no-craze glazes is a no-brainer. Anybody can do it. I
speak up for the tradtional ware fired in big woodkilns. Sometimes
glazed and sometimes not glazed, that I'd hate to see folks be fearful
of using.
There are also aesthetic reasons why folks fired in big
woodkilns that have some variability in the outcome of the surfaces of
the pots. These potters are very capable and could run circles
around most of us techinical wise.
>
> I am not starving this week so prefer to eat off paper plates
If you are afraid of crazing, shouldn't you be afraid of
bleached, porous paper? Have you "lemon tested" you paper plates?
>
> And yes, I'm still here, perfectly well, to tell you that I recently ate
> food, some served on crazed platters, gleefully and with total abandon. It
> was lovingly prepared by fellow students for lunches at school. A real
> godsend at the time.
>
I just ate part of my lunch of an unglaze shigaraki clay
anagama fired dish a potter in Kyushu gave me. It does have some
flyash glaze, it is only a drip that is a bit crazed where it is
thick. Folks who are used to toilet bowl, computer control fired
glazes might not understand the appeal of these pots. Mind you, I know
there is a place for both, but why do the toilet bowl crowd insist
that their way is the One True Way?
It also seems that folks who can't tell a good pot from a bad one
asethtically, fall back on technicalities: Things that don't required
an eye, but only a ruler. I find that very sad.
--
Lee Love in Minneapolis
http://mashikopots.blogspot.com/
http://claycraft.blogspot.com/
"Let the beauty we love be what we do.
There are hundreds of ways to kneel and kiss the ground." --Rumi
Lois Ruben Aronow on sun 27 jul 08
First off, I will be upfront about being the mom who uses spit and the tail
of my clay-crusted shirt to clean my kids bloody knees. I kiss my cat on
the lips, and will sometimes kiss a dog. I don't wear gloves on the subway,
although maybe I should. I have eaten sandwiches on the beach that are
covered in sand, and picnics in the park that flies have landed on. I also
own a divine set of commercial dinnerware I got in France that is wildly
crazed. On purpose.
So maybe my opinion doesn't count for much here, but I am a firm believer
against the over-sanitation of things today. I do believe trying to avoid
germs - which is the pastime in my gentrified neighborhood - is leading to
larger numbers of people becoming ill, rather than the other way around.
The human body is pretty nifty. It has a great relationship to the earth,
and develops immunity to many diseases and bacteria all on it's own. Funny,
that. If you take away this relationship, you increase the likely of
actually getting ill.
As for "primitive man" (thanks for the crack-up! I had a belly laugh)
crazed dinnerware was the least of the concerns for people who killed and
cooked food all at once, and stored it with no refrigeration. Oh, and they
probably ate with dirty hands. Forget "primitive". Even royals didn't
bathe on a regular basis until the 20th century. In many countries people
still don't.
And don't forget that "primitive man" live to the ripe old age of 30.
Maybe.
If you don't like crazed glazes, don't make them or buy them. But you have
a better chance of dying in a car crash than eating off a crazed plate.
...lo
Neon-Cat on sun 27 jul 08
Yo!
I just learned that the subject of crazing might not be a good thing to
discuss with potters. A valuable life lesson.
I'm gonna bail on this thread.
And Taylor, you're an intelligent and resourceful fellow. Nothing but your
own mindset prevents research. Who knows, maybe one day you'll even be
flowing along happily down those chemistry trails of life. For me to go
through notes and collect page after page of reference material for you is
just not what I want to do with my time and energy. Nor can I imagine you
wanting to read hundreds of pages of material on germs. It is kinda like a
bad dream...
And (shaking my head) does uncrazed ware really have to look like the inside
of a toilet, Lee? Yet more food for nightmares. Now I really feel the need
to invest in some spectacular crazed ware for a more satisfying dinnertime
experience. Boring paper plates pale (big time) in comparison to some of
your gorgeous pieces. Another life lesson: a tasty, nutritious meal on the
proper dinner service.
Thanks guys!
All the best to each of you and happy potting!
Marian
Kim Hohlmayer on mon 28 jul 08
I am coming in late and probably missed some important point in the conversation but I was taught to check for crazing by dipping part of the pot in a bucket of stirred up glaze. As the glaze dries the crazing becomes very obvious. --Kim H.
--- On Thu, 7/24/08, Ivor and Olive Lewis wrote:
> From: Ivor and Olive Lewis
> Subject: Re: Crazing Hazards. Verification ?
> To: CLAYART@LSV.CERAMICS.ORG
> Date: Thursday, July 24, 2008, 2:17 AM
> As far as I can see, using a matt glaze would conceal this
> defect, not
> eliminate it.
> It is a pity clay workers do not have access to the
> technology of the
> Metallurgist. They have a Dye Disclosure Test that is
> universally
> accepted as well as X-ray and Sonic methods for detecting
> internal
> flaws.
> Best regards,
> Ivor Lewis.
> Redhill,
> South Australia.
Larry Kruzan on mon 28 jul 08
****************
If you don't like crazed glazes, don't make them or buy them. But you have
a better chance of dying in a car crash than eating off a crazed plate.
...lo
*******************
As I was wasting a couple minutes in front of the TV last night, a person
placed the number of automobile crash deaths in the US at 43,000 (I did not
verify this) and the number of deaths by shark bites world-wide at 15. I
live in the center of the country but rarely hear news reports of an auto
accident in NYC or LA. But shark attacks always make the headlines.
Crazing, aside from aesthetics, or structural integrity, is the least of our
problems. I do believe if there was a traceable health problem we would
hear something about it, instead we get conjecture and dogma.
As for our immune systems, they are a wonderfully efficient system that (if
you are otherwise healthy) will most anything a person eats. I am always
amazed by the survival rate of dumpster divers. YUCK!!!!!!!!!!!
Larry Kruzan
Lost Creek Pottery
www.lostcreekpottery.com
Eleanor on mon 28 jul 08
Marian (Neon Cat) said:
> I just learned that the subject of crazing might not be a good thing
> to
> discuss with potters.
I used to glaze the insides of my mugs with Mastering^6 Glazes "Clear
Liner" but it crazed. Even after Ron graciously reformulated it for me
(he's so nice) it crazed.
I think crazing frightens average pottery users. They think something
is wrong with the pot.
I suspect that's why potters, including me, use dark-colored glazes
inside their pots. The user doesn't see any crazing and thus feels
secure.
Maybe, if this discussion continues, it should center on "safe colored
liner glazes".
Eleanor Kohler
(rain-saturated) Centerport, NY
Lee Love on mon 28 jul 08
On Sun, Jul 27, 2008 at 8:26 PM, Neon-Cat wrote:
> Yo!
> I just learned that the subject of crazing might not be a good thing to
> discuss with potters. A valuable life lesson.
It is a wonderful thing that potters love to talk about!
Look at these wonderfully crazed glazes:
http://www1.ocn.ne.jp/~ikiru/jshino.html
http://www.billboydceramics.com/blue_crackle_bowl_blowup.htm
Why would the glaze cops want to ban these?
--
Lee Love in Minneapolis
http://mashikopots.blogspot.com/
http://claycraft.blogspot.com/
"Let the beauty we love be what we do.
There are hundreds of ways to kneel and kiss the ground." --Rumi
pdp1@EARTHLINK.NET on mon 28 jul 08
Hi Lee, all,
If I ever get back into making Pots, I look forward to advertising them as
being "Guaranteed TO 'explode' or at least break pretty good, if put into a
freaking 'Microwave Oven" - or some-of-your Money back, if it does
not...less shipping and handling and a processing fee.
And I would work darn hard to ensure they would 'break' or 'explode', too,
testing testing testing till I had everything tweaked just 'right' for
reliable catastrophic failures if any one ever DID put one in and hit the
button...
I hate 'microwave ovens, and I wish everyone else did too...
I know!
A 'Gag' Mug, for the 'boss' or anyone one elected to enjoy the 'surprise',
looks just like a regular cheapy whatever Mug people have at-the-office,
but, put it in a 'microwave', hit the Button and "Kuh-Freakin'-Blooey!"
That'd be swell, and I bet they'd sell like 'Hotcakes' too..!
Love,
Phil
l v
----- Original Message -----
From: "Lee Love"
> On Sun, Jul 27, 2008 at 2:08 PM, Neon-Cat wrote:
>>
>>
>> If I were making dinnerware and cookware
Etc
Taylor Hendrix on mon 28 jul 08
Hey Marian:
I'll give you resourceful. I've been doing some preliminary searches
using our library's Ebso Health Source Academic Edition account and so
far limiting my searches to peer reviewed journals over the last 20
years, I have come up with no pertinent hits on these Boolean
searches:
glaze (unless you count all the denture articles, which may actually
be an interesting side step)
glaze and ceramics limits the above to the three articles on lead. Surprise.
glaze and bacteria returned bupkis.
bacteria and ceramics the same.
I have even widened my search to all available Ebsco databases and so
far have found nothing. I'm sure I will improve my search terms as I
go, but so far nothing specifically covering the question before us.
Rock on Neon-Mouser!
Taylor, in Rockport TX
On Sun, Jul 27, 2008 at 8:26 PM, Neon-Cat wrote:
> Yo!
> I just learned that the subject of crazing might not be a good thing to
> discuss with potters. A valuable life lesson.
> I'm gonna bail on this thread.
>
> And Taylor, you're an intelligent and resourceful fellow. Nothing but your
> own mindset prevents research.
...
Kim Hohlmayer on mon 28 jul 08
Hi Eleanor,
I would love a thread that followed that idea although I guess some might say that is why we should at the very least test until we get liners that don't craze and at the other extreme get a good education in creating our own glazes. :^) --Kim H.
--- On Mon, 7/28/08, Eleanor wrote:
> From: Eleanor
> Subject: Crazing Hazards. Verification ?
> To: CLAYART@LSV.CERAMICS.ORG
> Date: Monday, July 28, 2008, 10:26 AM
> Marian (Neon Cat) said:
>
> > I just learned that the subject of crazing might not
> be a good thing
> > to
> > discuss with potters.
>
> I used to glaze the insides of my mugs with Mastering^6
> Glazes "Clear
> Liner" but it crazed. Even after Ron graciously
> reformulated it for me
> (he's so nice) it crazed.
>
> I think crazing frightens average pottery users. They think
> something
> is wrong with the pot.
>
> I suspect that's why potters, including me, use
> dark-colored glazes
> inside their pots. The user doesn't see any crazing and
> thus feels
> secure.
>
> Maybe, if this discussion continues, it should center on
> "safe colored
> liner glazes".
>
> Eleanor Kohler
> (rain-saturated) Centerport, NY
Lois Ruben Aronow on mon 28 jul 08
Of course you do - and it's SHARK WEEK, too!!
ps - no lectures, anyone, about the dangersof my impending Jersey Shore
vacation. I will take my chances with both crazed ware AND the Atlantic
ocean.
> *******************
>
> As I was wasting a couple minutes in front of the TV last
> night, a person placed the number of automobile crash deaths
> in the US at 43,000 (I did not verify this) and the number of
> deaths by shark bites world-wide at 15. I live in the center
> of the country but rarely hear news reports of an auto
> accident in NYC or LA. But shark attacks always make the headlines.
>
Kim Hohlmayer on mon 28 jul 08
Hi Karin,
You are my hero. I could not have said it better. I sort of started this thread when I simply asked if crazing automaticly meant hazardous leaching. I got my answer and learned boat loads more about related subjects. It has been awesome. But now I think I'm getting more entertainment than education which is okay. I love clayart and the wonderful people who hold themselves up to public view and possible attack to share their knowledge and oppinions. Whether I agree, disagree or sit in complete confusion, thank you, especially the moderators. You are all saints.
--- On Sun, 7/27/08, Karin Givon wrote:
> From: Karin Givon
> Subject: Re: Crazing Hazards. Verification ?
> To: CLAYART@LSV.CERAMICS.ORG
> Date: Sunday, July 27, 2008, 1:51 PM
> I thought the ongoing ad inf thread was all to entertain us
> with a
> large variety of absurd thoughts. In case you hadn't
> noticed, clayart
> ABOUNDS with entertaining and even absurd thoughts! I
> Adore hearing
> from Taylor, from Lee, and John! And now even Vince! Who
> quotes
> Charlie Brown! You guys may be serious but I'm
> laughing my ___
> off . And the rest is so sweet, and helpful.
> I think we should canonize Mel, even if his beautiful
> pots are 98%
> inaccessible to a bunch of us. ( You can tell they're
> beautiful just
> from the rimd that show up on Visi for about 4 seconds)
> Anyway, I Love You Vince! That was the penultimate answer.
> Now we'll
> get to see who, besides the giggling woman, responds.
>
> Karin Givon
> DancingDragonPottery.net
>
> On Jul 26, 2008, at 7:43 PM, Vince Pitelka wrote:
>
> Steve Slatin wrote:
> > The equation is different than that, and expressed
> > in possibilities, not certainties. It's
> "persistent
> > odor demonstrates that something remains, something
> > may be (and I emphasize that 'may') a source
> of bacterial
> > infection, and some bacterial infections
> > are bad. My point, though, is a narrower one -- it
> > is that it is not possible to rationally
> > conclude that there is no risk based solely
> > on the fact that you have never heard tell
> > of the existence of the risk.
>
> AAAARRRRRGGGGHHHHH! (To quote Charlie Brown). To repeat,
> once more,
> (and
> forgive me for writing in capital letters, because I know
> they indicate
> that the writer is yelling. In this case, I AM YELLING!)
> THERE IS
> ABSOLUTELY NO DEMONSTRABLE PROOF OR EVEN THE SLIGHTEST
> INDICATION THAT
> THERE IS ANY RISK WHATSOEVER OF ILLNESS OR POISONING
> RESULTING FROM
> CRAZED
> GLAZES. NO ONE HAS EVER PUBLISHED THE SLIGHTEST WARNING OF
> ANY DANGER,
> AND LACKING THAT OVER THE PAST FEW CENTURIES, THE ONLY
> REASONABLE
> CONCLUSION IS TO AGREE THAT THERE SIMPLY IS ABSOLUTELY NO
> DANGER FROM
> CRAZED GLAZES.
>
> At this point, I cannot imagine any reason why someone
> would continue to
> post warnings about crazed glazes, except for the
> acknowledged concern
> that an unstable glaze inclined to release toxic substances
> might do so
> more quickly through craze cracks, although even that is
> unproven.
> Also,
> it has been understood throughout this conversation that a
> crazed glaze
> makes the fired product slightly weaker structurally.
>
> Otherwise, could we please stop wasting time on imaginary
> risks? There
> are way too many REAL risks in the world to engage in such
> a fool's
> mission.
> - Vince
>
> Vince Pitelka
> Appalachian Center for Craft
> Tennessee Technological University
> vpitelka@dtccom.net
> http://iweb.tntech.edu/wpitelka/
Ivor and Olive Lewis on tue 29 jul 08
Dear Kim Hohlmayer ,
What you describe may be an indication that a glaze will "Crawl" away
or across the surface of a pot as it is being fired due to high
surface tension and an inability of the molten glaze to wet the clay
surface.
The Fault being discussed is known as "Crazing" when it is a fault and
'Craquelle" when it is permitted as decoration. It is cause by a
mismatch of Coefficients of Thermal Contraction between Mature Glaze
and Mature Clay body.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
Ivor and Olive Lewis on tue 29 jul 08
I may be wrong here but I thought Microwave Ovens were designed with
an in built DE-Frosting program.
Is this so, and do they overcome the problem under discussion?
Best regards,
Ivor Lewis.
Redhill,
South Australia.
David Berg on tue 29 jul 08
Dear Ivor,
If you are asking whether the microwave oven will kill bacteria
hiding in crazed glazes, then the answer is yes, microwave
ovens can kill most non-spore forming bacteria after only
30 seconds exposure on the high setting.
I saw a publication that suggested that dry spores of Bacillus
subtilis required 45 minutes of microwaving to be killed. They're
tough.
David
David Berg
dberg2@comcast.net
http://bergstoneware.com/
On Jul 29, 2008, at 2:08 AM, Ivor and Olive Lewis wrote:
> I may be wrong here but I thought Microwave Ovens were designed with
> an in built DE-Frosting program.
> Is this so, and do they overcome the problem under discussion?
> Best regards,
> Ivor Lewis.
> Redhill,
> South Australia.
Ron Roy on thu 31 jul 08
Lee,
I would not say that cone 10 is easier - and find the alumina mattes to be
much harder to deal with at both temperatures because they are short of
silica - which makes them less stable as a class of glazes.
Recrystallized glazes are much harder to correct than glossy glazes -
because crystals are much more unpredictable.
Are you saying you are using matte glazes as liners?
RR
>Ron,
>
> It seems like non-high fire glossy has the most problems. You
>avoid much of the temperamental nature of cone 6 at higher temps.
>
>
>--
> Lee Love in Minneapolis
Ron Roy
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Ron Roy on thu 31 jul 08
Lee,
We do not explain how to cure crazing in our book - could it be you still
haven't read it?
There is a chapter on expansion which leads to a better understanding of
clay and glaze fit though.
And our glazes don't craze on most clay bodies - is that what you are
talking about?
RR
On Tue, Jul 22, 2008 at 11:13 PM, Ron Roy wrote:
> I do think that many potters don't know how to deal with crazing glazes
> which would be one explanation why there are so many crazed pots around and
> why so many potters are happy to put up with it.
>Ron,
>
> There is nothing "mystical" about it. But folks use it as a
>marketing tool to sell books.
>
>--
> Lee Love in Minneapolis
Ron Roy
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Ron Roy on thu 31 jul 08
Well it would for a while - till the staining showed it up - unless it was
a dark glaze. Still a better solution to fix the crazing.
RR
>On Thu, Jul 24, 2008 at 1:17 AM, Ivor and Olive Lewis
> wrote:
>> As far as I can see, using a matt glaze would conceal this defect, not
>> eliminate it.
>
>That was my point Ivor.
>
>--
> Lee Love in Minneapolis
Ron Roy
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Chuck T. Wagoner on thu 31 jul 08
>>Ron,
>> There is nothing "mystical" about it. But folks use it as a
>>marketing tool to sell books.
>>--
>> Lee Love in Minneapolis
I disagree with this vehemently because it was directed at a statement Ron
made. Ron and John have been so helpful to so many potters and ceramic
artists. They answer individual questions and spend hour's helping on the
Clayart list. It doesn't matter if you are a rank beginner or a recognized
Prof. of art. They help everyone.
This whole thread has been answered best by them by saying that the best way
to deal with crazing, whether it is or isn't dangerous, is to modify the
glaze or clay to eliminate the crazing. Unless the artist chooses to use
crazing as an aesthetic element, why not improve the strength and bacterial
resistance of your clay and glaze fit?
To many of us competent/working potters glazes and firing can seem a little
"mystical" at times. While I agree it is great to share glazes, how often do
those glazes come with and excellent manual on how to use, modify, apply,
fire and understand the individual characteristics of each glaze recipe?
I make pots that people use to eat from everyday and while it seems like
crazing is not a big deal it makes me feel good to have read Mastering Cone
6 Glazes" cover to cover. I want my pottery to be the best and safest it can
be.
The only thing that "markets" their book is that it is so good.
Long time Clayart Lurker
C.T. Wagoner
Rockville, IN
Billie Creek Pottery
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