Talbott on sun 8 jun 97
We have gotten a few mugs (12 or fewer) returned through the year by
customers saying that they poured hot water into their mug and it
cracked... We have generously replaced these mugs or refunded their money..
I have tested the mugs (cone 9/10 stoneware) at home by pouring steaming
hot water into these mugs time after time with no problems.. I am wondering
why these returned mugs have cracked... Could it be that these people are
taking a mug immediately after extremely cold tap water was poured out of
it and then poured boiling hot water into the mug? Or pour boiling hot
coffee out and then put ice-cold tap water back in to the mug.. causing
thermal shock... We use our own mugs all the time and never have had one
to fail... I really wonder if these people are being honest or if they
really are breaking the mug due to thermal shock...
A) Should I place a card in each mug warning against thermal shock and how
to avoid doing so... and state that the mugs are not guaranteed against
such breakage.
B) Should I continue to warranty these mugs against breakage... 99.9% of
our customers are honest but there is always the 0.1% that is not...
C) Could anyone share their return/guarantee policies that deal with such
things... I know of one big and famous pottery in Edgecomb, Maine that
only offers store credit within 14 days of purchase and they are certainly
successful...
Your opinions would be appreciated... Marshall
1ST ANNUAL CLAYARTERS' GALLERY - NAPLES, MAINE (Summer 1997)
http://fmc.utm.edu/~dmcbeth/cag/naples.htm
Celia & Marshall Talbott, Pottery By Celia, Route 114, P O Box 4116,
Naples, Maine 04055-4116,(207)693-6100 voice and fax,(call first)
WBS Live Chat Room, Sat Nites 10 PM EDT, Private Room: Clayarters
Jonathan Kaplan on sun 8 jun 97
Marshall: I might suggest that you contact the Orton Foundation and send
them a sample of yuour clay body for a DTA test. This test will reveal,
quite dynamically, the endothermic and exothermic peaks, the quartz
inversions, etc. etc and will indicate to you if there is free silica in
your clay formula.
Don't go blindly into the maket place with ware that may not be stable. If
only a few customers experience problems, it may be an indication of
something larger that could pose deep problems for you. I'd be happy to
look over your clay formula and make some recommendations if you would
like.
You also might check out
http://www.ceramicsoftware.com/education/clay/kaplan1.htm as well as Tony
Hanson's entire web page regarding clays.
Jonathan
Jonathan Kaplan http://www.craftweb.com/org/jkaplan/cdg.shtml
http://www.ceramicsoftware.com/education/clay/kaplan1.htm
jonathan@csn.net
Ceramic Design Group Ltd./Production Services Voice:
970-879-9139 POB 775112
FAXmodem: same
Steamboat Springs, Colorado 80477, USA CALL before faxing
"
Paul Kaplan on sun 8 jun 97
Talbott wrote:
>
> ----------------------------Original message----------------------------
> We have gotten a few mugs (12 or fewer) returned through the year by
> customers saying that they poured hot water into their mug and it
> cracked... We have generously replaced these mugs or refunded their money..
>
> I have tested the mugs (cone 9/10 stoneware) at home by pouring steaming
> hot water into these mugs time after time with no problems.. I am wondering
> why these returned mugs have cracked... Could it be that these people are
> taking a mug immediately after extremely cold tap water was poured out of
> it and then poured boiling hot water into the mug? Or pour boiling hot
> coffee out and then put ice-cold tap water back in to the mug.. causing
> thermal shock... We use our own mugs all the time and never have had one
> to fail... I really wonder if these people are being honest or if they
> really are breaking the mug due to thermal shock...
>
> A) Should I place a card in each mug warning against thermal shock and how
> to avoid doing so... and state that the mugs are not guaranteed against
> such breakage.
>
> B) Should I continue to warranty these mugs against breakage... 99.9% of
> our customers are honest but there is always the 0.1% that is not...
>
> C) Could anyone share their return/guarantee policies that deal with such
> things... I know of one big and famous pottery in Edgecomb, Maine that
> only offers store credit within 14 days of purchase and they are certainly
> successful...
>
> Your opinions would be appreciated... Marshall
>
> 1ST ANNUAL CLAYARTERS' GALLERY - NAPLES, MAINE (Summer 1997)
> http://fmc.utm.edu/~dmcbeth/cag/naples.htm
>
> Celia & Marshall Talbott, Pottery By Celia, Route 114, P O Box 4116,
> Naples, Maine 04055-4116,(207)693-6100 voice and fax,(call first)
> WBS Live Chat Room, Sat Nites 10 PM EDT, Private Room: Clayarters
Have you considered the possibility that your customers may have heated
liquids in the mug in a microwave? It is my understanding that
microwaving will heat the metallic elements in the glaze and/or the clay
at different rates creating stresses. I have always advised customers
against microwaving my pottery, just oven and dishwasher safe. Any
comments or experiences will be appreciated.
Marilyn Price
Ric Swenson on sun 8 jun 97
First, ask a couple questions....
Are they glazed inside AND outside? If only inside there could be a stress
created between the inside and outside that leaves a weakness that thermal
expansion won't handle. Larger pieces, like lasagna dishes exposed to
broiler heat are more likely to dunt/crack than a mug. Is it ONE type
glaze that always seems to be the culprit? Are the ones that fail always
the ones unloaded first...near the door?
IMHO
It is possible that the people might have (un-knowingly) tapped the mug in
the sink...or loaded carelessly in the dishwasher and caused a
crack...which didn't show or open up until hot water expanded the mug
suddenly. I have seen this happen in my own experience.
If you cannot MAKE it happen to your wares, then you might look for cold
drafts in your cooling cycle (near door/ports) as a possibility.
Or
Ask if the customer used direct heat...to reheat coffee/tea (ie. heated it
up on the stove top...with the new glass top stoves some people might think
that is okay to do....but it probably would break anyones mugs.)
I would suspect the tapping/clanking together at the lip during cleaning as
the most likely...if you can't find dunting, from your kiln's wares cooling
too quickly.
In the spirit of good customer relations, (engage the customer in helping
to find what the problem might be?)...Continue to replace any defect like
that...but don't stop looking for the reason(s).
Hope this helps.
Happy Potting!
Ric Swenson
>----------------------------Original message----------------------------
>We have gotten a few mugs (12 or fewer) returned through the year by
>customers saying that they poured hot water into their mug and it
>cracked... We have generously replaced these mugs or refunded their money..
>
>
>I have tested the mugs (cone 9/10 stoneware) at home by pouring steaming
>hot water into these mugs time after time with no problems.. I am wondering
>why these returned mugs have cracked... Could it be that these people are
>taking a mug immediately after extremely cold tap water was poured out of
>it and then poured boiling hot water into the mug? Or pour boiling hot
>coffee out and then put ice-cold tap water back in to the mug.. causing
>thermal shock... We use our own mugs all the time and never have had one
>to fail... I really wonder if these people are being honest or if they
>really are breaking the mug due to thermal shock...
>
>A) Should I place a card in each mug warning against thermal shock and how
>to avoid doing so... and state that the mugs are not guaranteed against
>such breakage.
>
>B) Should I continue to warranty these mugs against breakage... 99.9% of
>our customers are honest but there is always the 0.1% that is not...
>
>C) Could anyone share their return/guarantee policies that deal with such
>things... I know of one big and famous pottery in Edgecomb, Maine that
>only offers store credit within 14 days of purchase and they are certainly
>successful...
>
>Your opinions would be appreciated... Marshall
>
> 1ST ANNUAL CLAYARTERS' GALLERY - NAPLES, MAINE (Summer 1997)
> http://fmc.utm.edu/~dmcbeth/cag/naples.htm
>
> Celia & Marshall Talbott, Pottery By Celia, Route 114, P O Box 4116,
> Naples, Maine 04055-4116,(207)693-6100 voice and fax,(call first)
> WBS Live Chat Room, Sat Nites 10 PM EDT, Private Room: Clayarters
Ric Swenson, Bennington College, Route 67-A, Bennington, VT 05201-6001 ph
802 442-5401 vox 262 fax 237 direct fax line 802 442-6164 or
email rswenson@bennington.edu
gshaffer on mon 9 jun 97
marshall, i would be carefully considering your clay body for possible
crystobilite growth. intermittent problems with thermal shock might be
an indicator. if you do not have at least 10 % feldspar in your body you
may not be turning all the free silica into glass or absorbing it in and
that might be it. good luck , gary
Talbott on mon 9 jun 97
Marilyn...We put our mugs in a microwave frequently to the point of boiling
water with no problems.... We think that the problem arises with just one
glaze combination... If there is indeed a thermal expansion problem at
all... today we placed a mug in the freezer for 20 minutes and remove it
and immediately poured boiling water into it.. and there was NO problem.. I
think the problem maybe customers on occasion drop mugs and want them
replaced.. but I will keep testing just in case... (24 hours in the freezer
and then boiling water immediately... ...will let you know what happens!)
Marshall
>Have you considered the possibility that your customers may have heated
>liquids in the mug in a microwave? It is my understanding that
>microwaving will heat the metallic elements in the glaze and/or the clay
>at different rates creating stresses. I have always advised customers
>against microwaving my pottery, just oven and dishwasher safe. Any
>comments or experiences will be appreciated.
>Marilyn Price
1ST ANNUAL CLAYARTERS' GALLERY - NAPLES, MAINE (Summer 1997)
http://fmc.utm.edu/~dmcbeth/cag/naples.htm
Celia & Marshall Talbott, Pottery By Celia, Route 114, P O Box 4116,
Naples, Maine 04055-4116,(207)693-6100 voice and fax,(call first)
WBS Live Chat Room, Sat Nites 10 PM EDT, Private Room: Clayarters
Bill Walker on mon 9 jun 97
>We have gotten a few mugs (12 or fewer) returned....by customers saying
they poured hot water into their mug and it cracked....
I think if you have had several different customers with the same
story, then it is likely that the cracks are forming just as they
describe.
What do the cracks look like? Are they a ring around the bottom,
or a line up the side? Are they related to the placement of the
handle? Is there a single crack or several radiating from a single
point? And what sort of clay body do you use?
Bill Walker
Alfred NY
walkerw@bigvax.alfred.edu
Terrance Lazaroff on wed 11 jun 97
I have made mugs that work very well. Yet when I take the mug and second
glaze it an fire them to the same cone they crack at the base with thermal
shock. I believe that the second firing fluxed the clay to the point that it
became more viterous thus it performed the same as if we were pouring boiling
water into a glass cup. I suggest you add instructions to treat your mugs
the same as a glass cup. The method used to stop thermal shocking in glass
cups is to put a spoon into the cup prior to pouring in boiling water.
Good Luck
Terrance
Ron Roy on thu 12 jun 97
>----------------------------Original message----------------------------
>I have made mugs that work very well. Yet when I take the mug and second
>glaze it an fire them to the same cone they crack at the base with thermal
>shock. I believe that the second firing fluxed the clay to the point that it
>became more viterous thus it performed the same as if we were pouring boiling
>water into a glass cup.
The second firing of ware insures there will be more cristobalite in a
body. The reason these mugs cracked is because - as the cristobalite goes
through its inversion (gets smaller on cooling and larger when heated)
between 150C and 250C. As the body contracts - if the glaze is such that is
stops the body - enough - from getting smaller - stresses are set up that
will crack the pot in the kiln or later - specifically when something hot
is poured in. This expands the glaze a little - if there is enough stress
resident the pot will crack.
The reason it happens in twice fired pots more - cristobalite starts to
form in bodies about 1100C. There is only a little at first but the higher
and longer you fire the more it builds up. The slower you cool the more it
builds up. The second firing continues this process. If there is any
cristobalite from the first firing there will be more after the second. How
to avoid excessive amounts of cristobalite - make sure there is enough
sodium and potassium around to melt it as it forms - that means at least
10% spar in your body.
It will not happen with a crazed glaze - glaze winds up smaller than the
body - so I can also say the fault is conditional on the
expansion/contraction of the glaze. Glazes with a lower
expansion/contraction than the body will contribute to this particular
dunting problem. I should add - the problem has more to do with
cristobalite - you can have glazes which will not craze because their
expansion/contraction is low enough and still not crack - even with many
freezing and boiling cycles - however - throw enough cristobalite into the
mix and you reach a dead end.
Those of you who are interested in understanding this process will find a
series of articles (3) in Contact magazine. The first will appear in the
next issue and explains what a dilatometer does and how the information
obtained is useful to anyone trying to melt two or more materials together.
Ron Roy
Toronto, Canada
Evenings, call 416 439 2621
Fax, 416 438 7849
Studio: 416-752-7862.
Email ronroy@astral.magic.ca
Home page http://digitalfire.com/education/ronroy.htm
Leonard Christopher on thu 12 jun 97
Talbott wrote:
>
> ----------------------------Original message----------------------------
> We have gotten a few mugs (12 or fewer) returned through the year by
> customers saying that they poured hot water into their mug and it
> cracked... We have generously replaced these mugs or refunded their money..
>
> I have tested the mugs (cone 9/10 stoneware) at home by pouring steaming
> hot water into these mugs time after time with no problems.. I am wondering
> why these returned mugs have cracked... Could it be that these people are
> taking a mug immediately after extremely cold tap water was poured out of
> it and then poured boiling hot water into the mug? Or pour boiling hot
> coffee out and then put ice-cold tap water back in to the mug.. causing
> thermal shock... We use our own mugs all the time and never have had one
> to fail... I really wonder if these people are being honest or if they
> really are breaking the mug due to thermal shock...
>
> A) Should I place a card in each mug warning against thermal shock and how
> to avoid doing so... and state that the mugs are not guaranteed against
> such breakage.
>
> B) Should I continue to warranty these mugs against breakage... 99.9% of
> our customers are honest but there is always the 0.1% that is not...
>
> C) Could anyone share their return/guarantee policies that deal with such
> things... I know of one big and famous pottery in Edgecomb, Maine that
> only offers store credit within 14 days of purchase and they are certainly
> successful...
>
> Your opinions would be appreciated... Marshall
>
> 1ST ANNUAL CLAYARTERS' GALLERY - NAPLES, MAINE (Summer 1997)
> http://fmc.utm.edu/~dmcbeth/cag/naples.htm
>
> Celia & Marshall Talbott, Pottery By Celia, Route 114, P O Box 4116,
> Naples, Maine 04055-4116,(207)693-6100 voice and fax,(call first)
> WBS Live Chat Room, Sat Nites 10 PM EDT, Private Room: Clayarters
Perhaps your customers are putting the mugs in a microwave. After
extensive use, I have had pieces just snap--a very clean break. The
only thing I could ever come up with is they had been used in a
microwave. I know most potters indicate that pottery can be used in a
microwave, but I think it may change something in the molecular
structure?????
Talbott on fri 13 jun 97
Leonard Christopher
I don't think that is the problem since we microwave in our wares on daily
basis without any problems...
>Perhaps your customers are putting the mugs in a microwave. After
>extensive use, I have had pieces just snap--a very clean break. The
>only thing I could ever come up with is they had been used in a
>microwave. I know most potters indicate that pottery can be used in a
>microwave, but I think it may change something in the molecular
>structure?????
1ST ANNUAL CLAYARTERS' GALLERY - NAPLES, MAINE (Summer 1997)
http://fmc.utm.edu/~dmcbeth/cag/naples.htm
Celia & Marshall Talbott, Pottery By Celia, Route 114, P O Box 4116,
Naples, Maine 04055-4116,(207)693-6100 voice and fax,(call first)
WBS Live Chat Room, Sat Nites 10 PM EDT, Private Room: Clayarters
Evan Dresel on mon 16 jun 97
At 07:17 PM 6-12-97 EDT, you wrote:
>----------------------------Original message----------------------------
>>----------------------------Original message----------------------------
Snip... Ron Roy explains why increased crystobalite leads to cracking of
thermal shocked mugs...
>It will not happen with a crazed glaze - glaze winds up smaller than the
>body - so I can also say the fault is conditional on the
>expansion/contraction of the glaze. Glazes with a lower
>expansion/contraction than the body will contribute to this particular
>dunting problem. I should add - the problem has more to do with
>cristobalite - you can have glazes which will not craze because their
>expansion/contraction is low enough and still not crack - even with many
>freezing and boiling cycles - however - throw enough cristobalite into the
>mix and you reach a dead end.
>
Snip some more...
>Ron Roy
So if you are willing to accept the perceived risk of bacterial growth in
crazed pots (which I question) and the decreased strength (which I don't)
this seems to suggest that crazing may be somewhat advantageous. If I
recall past discussions and my geochemistry correctly, crystobalite is the
stable form of silica at stoneware temperatures so the addition of alkali is
basically inhibiting the kinetics (rate) of crystobalite formation so you
are working against thermodynamics trying to enhance the unstable quartz
form. I have no real problem with that except that some of us have little
control over our clay body composition and that it complicates the
production (maybe I shouldn't soak my glazes because it will give more time
at high T for crystobalite to form).
The perfect clay-glaze combination seems to be a mirage receding into the
distance.
Evan Dresel who is trying to get Ron's goat only a little.
pedresel@3-cities.com
Ron Roy on tue 17 jun 97
Hi Evan,
You are not getting my goat at all. In fact I know there are many who find
this subject intimidating and I welcome any chance to clarify.
In fact as I wrote about cristobalite and crazing I anticipated the
question. I mentioned it as a way of helping the understanding of this
process.
A crazed glaze (has spaces between cracks) can absorb the stresses that
cristobalite puts on glaze. The reason a pot cracks or shivers because the
glaze winds up too big is because there is no place for the stress to go.
>So if you are willing to accept the perceived risk of bacterial growth in
>crazed pots (which I question) and the decreased strength (which I don't)
>this seems to suggest that crazing may be somewhat advantageous.
I did not mean that. I was trying to shed some light on the process. I must
say I would prefer crazing in mine and others pots to cracking however. I
agree about the reduced strength of crazed pots. You can still solve the
problem by dropping the glaze expansion just below the crazing point - just
enough to prevent crazing in most cases. There are some bodies that have so
much cristobalite the window is very small.
How to find clay that has no (or a small amount) of cristobalite. Jim
Robinson wrote two articles on this subject in the Studio Potter years ago.
In the June 1988 issue (vol. 16 #2) you will find "Body Building for
Potters." He is a pioneer in this important area and if you can find a copy
read it.
>If Irecall past discussions and my geochemistry correctly, cristobalite is the
>stable form of silica at stoneware temperatures so the addition of alkali is
>basically inhibiting the kinetics (rate) of cristobalite formation so you
>are working against thermodynamics trying to enhance the unstable quartz
>form.
There are three forms of silica in our bodies. Melted (amorphous) which
gives a low but steady rate of expansion/contraction. Quartz, a crystalline
form which goes through a reversible inversion at 573C - not a problem for
most of us because are glazes are still soft enough to adjust to the change
in volume and it only has to go through that inversion once - on the way
down during cooling. Cristobalite goes through it's inversion between 250C
and 150C when the glaze is really solid. Lets say the glaze already has a
lower contraction on cooling than the body (at 250C) and has created some
stress - it then has to contend with the extra contraction as the body goes
through the extra downward volume change due to the cristobalite. Add to
this that pots meant for the oven have to go back and forth through this
cristobalite conversion in use. What having enough feldspar in the body
does is melt the minute particles of silica which are the seeds of further
cristobalite production. The simple formula is - make sure you have at
least 10% feldspar in your body. I have done about ten dilatometer
measurements of porcelain. Have yet to find any cristobalite. Porcelains
have well over 10% feldspar.
Then there is the problem of glazes with low expansion/contraction. They
can break pots made of clay that has no cristobalite (anything fired below
1100C and those bodies above which have no cristobalite) simply because
there is too much of a difference in expansion/contraction. Combine the two
(cristobalite and low expansion glaze) and you have problems waiting to
happen.
>I have no real problem with that except that some of us have little
>control over our clay body composition and that it complicates the
>production.
I agree and all I can offer at the moment is: Ask your supplier to give
you a list of their bodies with the amounts (%) feldspar in them. Use
porcelain. Avoid clays with iron in them if you are firing in reduction -
they are the worst offenders but not the only ones. Have your glazes
checked for expansion. I have been able to spot the offenders with some
accuracy. Use the same glaze inside and out - the stress is compensated for
up (or should I say down) to a certain point. Test all your combinations
and find out where the problem is. Don't put a crazing glaze on the outside
and a low expander on the inside. The fastest way to spot low expanding
glazes is to glaze a thin cylinder (no bottom) inside only applying the
glaze a little thicker than normal. Freeze and boiling water if they are
not cracked already.
(maybe I shouldn't soak my glazes because it will give more time
>at high T for cristobalite to form).
Or crash cool to 1100C after a short soak. I don't have much faith this
will change much but it may save some borderline situations.
>The perfect clay-glaze combination seems to be a mirage receding into the
>distance.
I see it a different way. We have ignored the technical to the point of
absurdity. We are only reaping the inevitable consequences of our attitude.
Those who make our clays, for the most part, are as uneducated as we are.
If Jim had gotten the attention he deserved 10 years ago we would not be in
such state. It is getting better. I have a dilatometer and I work for two
clay companies and am applying what I am learning. Tony Hansen is
purchasing my measurements of Plainsman clay bodies and posting them on the
inter net. Contact magazine is publishing the first of three articles on
dilatometry. There are magazines devoted to technical aspects of our craft.
Glaze calculation software has put the molecular formulas within easy grasp
of anyone. All we need to do it start thinking and acting like people who
use heat to make chemical changes every time we fire a kiln.
Guess you did get my goat Evan - maybe even a few of them and I must say in
a very nice way. Thanks.
Ron Roy
Toronto, Canada
Evenings, call 416 439 2621
Fax, 416 438 7849
Studio: 416-752-7862.
Email ronroy@astral.magic.ca
Home page http://digitalfire.com/education/ronroy.htm
Cindy on tue 17 jun 97
Ron,
If I use the same glaze base with a variety of oxide combinations to obtain
my colors, is it then acceptable in terms of expansion, strength, etc. to
use a different color inside the mug from the one on the outside?
Just wondering,
Cindy Strnad
Ron Roy on fri 20 jun 97
Hi Cindy - I'll just carefully avoid making any definative answer here and
say it depends.
I have no experience with cone 6 colored glazes to base my opinion on but I
will say small amounts of stain will have a small effect on expansion.
Whats small? up to 5% lets say. If you use larger amounts you can test to
see if there will be a problem. Just use your mugs - maybe make em a little
thinner than you usually do and try the combinations you are thinking of
using. Then do the freezing boiling thing.
Sounds like I am avoiding the question but what we don't know is how close
your glaze is to a misfit in either direction. If you are close then even a
5% addition of stain might tip you over. Remember - if you are trying to
find a mismatch - thinner than usual clay and thicker than usuall glaze
will find it quick. I should add I don't mean real thick - I mean a little
thicker.
When I find myself talking about this I always remember a line from the
Hamer book. Functioal potters find it better to be closer to crazing than
to dunting.
The other line I think of quite often is " anyone can work with good clay."
They were explaining the difference between a professional attitude and an
amateur attitude I think.
>----------------------------Original message----------------------------
>Ron,
>
>If I use the same glaze base with a variety of oxide combinations to obtain
>my colors, is it then acceptable in terms of expansion, strength, etc. to
>use a different color inside the mug from the one on the outside?
>
>Just wondering,
>
>Cindy Strnad
Ron Roy
Toronto, Canada
Evenings, call 416 439 2621
Fax, 416 438 7849
Studio: 416-752-7862.
Email ronroy@astral.magic.ca
Home page http://digitalfire.com/education/ronroy.htm
Talbott on sat 21 jun 97
I still am of the opinion that placing a mug in a freezer for 24
hours (freezer temp at 0 to -5 Fahrenheit) and then pour boiling water into
the mug to see whether or not it will crack is a "little extreme" and still
unreliable to the point:
(a) At what rate do you pour the boiling water in the mug ie.. really slow
or really fast...(rate should be measure ie.. in ml per second) as
example...
(b) What is the temp of the freezer?
(c) Is the mug glazed on the bottom or unglazed on the bottom
(d) etc... etc...
I would like to know if anyone has actually done a controlled experiment on
this... As in SCIENTIFIC... this is dealing with coefficients of
expansion..true... should we go to fused quartz for our claybodies to allow
our wares to pass this test?...
I would like to know of some "basic guide lines" which would enhance the
durability of pottery (cone 10 reduction ..glazed on all surfaces except
for the very bottom.. for me)..
Example: 1) Place 10% of feldspar in the claybody..etc...
Are there other suggestions.... Marshall
1ST ANNUAL CLAYARTERS' GALLERY - NAPLES, MAINE (Summer 1997)
http://fmc.utm.edu/~dmcbeth/cag/naples.htm
Celia & Marshall Talbott, Pottery By Celia, Route 114, P O Box 4116,
Naples, Maine 04055-4116,(207)693-6100 voice and fax,(call first)
WBS Live Chat Room, Sat Nites 10 PM EDT, Private Room: Clayarters
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