Jan 3rd, '11, 18:30
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Re: The Official "Ask the Artisan" Community Topic

by Firebug Pottery » Jan 3rd, '11, 18:30

So did your pots come out of the kiln yet? Do any good?

Jayme

Jan 12th, '11, 13:36
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Re: The Official "Ask the Artisan" Community Topic

by dsebs » Jan 12th, '11, 13:36

What do you guys feel is the best way to start getting into ceramics? Taking a course at a university? Reading books? Learning from someone that is an expert? Etc., etc. I'm interested in getting started as a hobby and possibly more, but I'm not sure where would be best to start.

Thanks in advance :)

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Jan 12th, '11, 16:25
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Re: The Official "Ask the Artisan" Community Topic

by JBaymore » Jan 12th, '11, 16:25

dsebs,

There are many avenues to get started learning clay. There is no "right" answer for everyone.

Since you are thinking "hobby", there likely is no need to get involved in a matriculated program at a college or university....... unless there is no other resource available to you. However, a college level program might have resources and an environment which you won't find at a community ed center on in a private potter's studio..... and likely a more rigourous approach.

But working one-on-one in a private potter's studio will offer you things that a college program does not too.

Once you get involved....... assess your own needs and don't be afraid to change the venue if you feel that the one you have chosen is not working for you.

Above all....... just jump in a give clay a try. Likely you'll get "hooked" very quickly. ("Beware the Dark Side. You have no idea of the power it has!")

best,

................john

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Jan 12th, '11, 18:34
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Re: The Official "Ask the Artisan" Community Topic

by togei » Jan 12th, '11, 18:34

Hello Jayme,
I didn't see your question until now, sorry.
Yes, they came out ok. I was happy enough to make another kiln load I am now drying. The mixed porcelain I like but it is what I call very weak tea. Some people like it but for me I prefer something stronger, in other words it is probably a learned taste. I am using a mixed porcelain cup for my tea as I write. It is smooth and nice to the touch but every time I pick it up I think it needs something to complete the circle. That fits my work perfectly as I do believe work isn't complete until it is in use.

To answer the question about how to get started.
If you can get a hold of a cheap kiln or at least the 'free' use of one I think that is the best. There are many tools that can be acquired but really you need the desire and at the least a kiln. You can start making things with your hands until you get something else to make them with.
My two yen,
Dave

Jan 13th, '11, 12:29
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Re: The Official "Ask the Artisan" Community Topic

by Firebug Pottery » Jan 13th, '11, 12:29

Hey guys, I have a random question- I am doing some research for the university, and was wondering if anyone knows about raku- not the Paul Soldner version (as much as we love it and miss him) but the real, use-able version? What kind of glazes are used, and to what temperature?

Curious there's not more info out there....

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Jan 15th, '11, 18:57
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Re: The Official "Ask the Artisan" Community Topic

by togei » Jan 15th, '11, 18:57

I don't know a lot of details. I think it is about 800 degrees Celsius. I think it was traditionally made with Kamogawa stone. I do know there is an exhaustive and scholarly book by Morgan Pitelka, see http://unc.academia.edu/MorganPitelka/Books I have neither met him nor read the book.
Dave

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Jan 18th, '11, 12:12
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Re: The Official "Ask the Artisan" Community Topic

by hopeofdawn » Jan 18th, '11, 12:12

Okay, I've been wondering about this for a while, and hopefully the experts here can enlighten me ...

I've recently been introduced (and fallen in love with) celadon ware. I know celadon glazes can range a great deal in color depending on the oxidation (?) of the firing, but that they should always have some crackling in the glaze. I've also seen many other (non-celadon) pieces (usually modern) with different kinds of crackled glazes as well. So I'm wondering--is there any difference in how the crackling is produced in a celadon glaze? Basically, what makes celadon so unique/difficult to work with?

Inquiring minds wanna know .... :)

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Jan 18th, '11, 13:39
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Re: The Official "Ask the Artisan" Community Topic

by JBaymore » Jan 18th, '11, 13:39

Actually celadon glazes are no nore difficult to work with than most other glazes. The supposed "difficulty" is a marketing myth. (Works , doesen't it? :wink: )

The color in celadon glazes comes from a small inclusion of iron oxide in the basically transparent or semi-transparent glaze batch. When fired in reduction conditions, the iron is reduced to the FeO state, changing it to a flux on the silica base of the glaze and this also causes the grey-green to bluish coloration of the fired celadon glaze.

Getting the "best" possible colors and surfaces out of ANY glaze is truly difficult.... but that is true of ALL glazes.....not just celadons.

The tendency to go from blue colors to green colors is based upon the chemistry of the base glass combined with the percentage of iron present. For example, small molecular equivalents of BaO present in the glaze melt combined ith about .5% iron ocide by weight will help to promote a bluish color, particlauiry in a Na2O fluxed glass. Celadons can run from ice blue to almost a smoky green.

All that is necessary to produce celadon is between .25% and about 3.5% red iron oxide in the batch and then firing it in reducing conditions before the glaze surface becomes gas impermeable to the reducing agents CO (and or H). This iron can come as an addition of pure red iron oxide, or can come from an iron bearing clay material.

As to the "crackling"... this is actually a glaze "defect" called crazing. When you WANT it for visual effect...... you call this defect a "feature" :wink: . It comes whern the frozen glaze (glass is actually a liquid... a supercooled liquid) has a coefficient of reversible thermal expansion (COE) that is greater than the underlying clay body.

On cooling in the kiln, the glaze then shrinks more than the clay body under it. Glass is strong in compression but quite weak in tension. The cracks are the glass fracturing to absorb the stresses of the tension created. Technically these cracks actually penetrate just slightly into the glaze/body interface layer.... and crazed wares are weaker than their non-crazed counterparts.

The museum curator's "yellow celadon" you sometime see labeled as a special category is just regular celadon glazes that have been fired in oxidation, not reduction. I am guessing that these pieces MAY have actually been "seconds" from the potter's point of view...... should have been celadon color :lol: .

And no... they are not supposed to always have crazing in them. The best of them fit the underlying bodies perfectly. Take a look a the work of Shimada Fumio as a good example of this (and some stunning celadon on porcelain work).

Hope this helps.

best,

...........john

Jan 19th, '11, 12:34
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Re: The Official "Ask the Artisan" Community Topic

by Firebug Pottery » Jan 19th, '11, 12:34

I think the only part of celadons I've really had a hard time with are the ones that have the hexagonal crackles, like those produced by Ikai Yuichi, which he calls "seiji celadon" I can't help but feel that these are not just the result of a thick application, but also a controlled cooling, allowing time for true minerals to form. Any thoughts on that type of crazing? I've also always heard that titanium impurities lend to more green color, (along with increased iron) but I'm more of a tenmoku glazer, so don't really know from experience.

Jayme

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Re: The Official "Ask the Artisan" Community Topic

by hopeofdawn » Jan 19th, '11, 12:52

Wow, what a great explanation--thank you very much! I suddenly feel very edumacated ... :D

So I guess the only question I have left is how would someone (who wasn't a ceramicist) be able tell a celadon glaze from pieces using other (similar) blue-green-gray glazes? Or do all glazes in that color range require red iron oxide in the glaze mix, and thus are 'celadon' by default?

Basically--is there such a thing as a particular celadon glaze recipe/technique, as it were, that a ceramic artist would use to make 'authentic' celadon, as opposed to any number of blue/green commercial glazes out there? Or is 'celadon' simply more of a color description--like 'puce' or 'ivory'--that can be applied to any number of different glazes?

Jan 24th, '11, 19:00
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Re: The Official "Ask the Artisan" Community Topic

by masimmo » Jan 24th, '11, 19:00

dsebs wrote:What do you guys feel is the best way to start getting into ceramics? Taking a course at a university? Reading books? Learning from someone that is an expert? Etc., etc. I'm interested in getting started as a hobby and possibly more, but I'm not sure where would be best to start.

Thanks in advance :)

I got into ceramics from taking an introduction to the wheel course at a local museum one summer. I feel in love with clay then, and started taking clay classes at college that fall. Classes at local museum or clay center are probably a lot cheaper then a class at a university. I've been to a couple really good workshops too. Ceramics Monthly has a pretty extensive list of workshops: http://ceramicartsdaily.org/ceramics-mo ... _workshops

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Jan 24th, '11, 19:33
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Re: The Official "Ask the Artisan" Community Topic

by JBaymore » Jan 24th, '11, 19:33

hopeofdawn wrote:So I guess the only question I have left is how would someone (who wasn't a ceramicist) be able tell a celadon glaze from pieces using other (similar) blue-green-gray glazes? Or do all glazes in that color range require red iron oxide in the glaze mix, and thus are 'celadon' by default?

Basically--is there such a thing as a particular celadon glaze recipe/technique, as it were, that a ceramic artist would use to make 'authentic' celadon, as opposed to any number of blue/green commercial glazes out there? Or is 'celadon' simply more of a color description--like 'puce' or 'ivory'--that can be applied to any number of different glazes?
"Traditional" celadon involves a feldspathic (heavily sourced from feldspar) high fired glaze (in the 1200-1300 C range) containing iron oxide from some source (as a "contaminant" in a raw material like some red clay or as a deliberate separate addition) and a reduction atmosphere in a fuel burning kiln of some sort to cause the color to develop. That might be what you'd call "authentic".

The ARE available to ceramists what are called commercial glaze stains that are "celadon" in coloration. They are not necessarily relying on only reduced iron oxide to get the stable color; it might be sourced from many other coloring oxides. These stains can be added to a clear glaze base and produce a color that to a lot of folks would be pretty much indistinguishable from a "real" celadon. These glazes could be fired in oxidation in something like an electric kiln; no reduction required. They could also be achieved at lower temperatures than the "traditional" process.

The "best of the best" celadons have a quality of glaze surface and a depth of color that "sings". Knock your socks off. More "average" celadons are nice... but could be "faked" as far as the eye of the non-ceramist is concerned.

Ceramics is a complex field. The correct answer to any question about ceramics is, "It depends". :wink:

best,

................john

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Jan 25th, '11, 19:19
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Re: The Official "Ask the Artisan" Community Topic

by Petr Novák » Jan 25th, '11, 19:19

Hi John,

I always enjoy reading your commentary or explanations around here...it is very often what I would like to say if I could talk more freely in English (As potter I know but as not native speaker it is hard to explain it so clearly for me..) You are teacher, are not you?

Petr

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Re: The Official "Ask the Artisan" Community Topic

by JBaymore » Jan 25th, '11, 22:32

Petr Novák wrote:You are teacher, are not you?
Petr,

Thanks for the kind words. Yup........ studio artist and PT ceramics professor at an art college. Been teaching at the college level since the mid 70's.

best,

................john

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Re: The Official "Ask the Artisan" Community Topic

by hopeofdawn » Jan 26th, '11, 11:53

JBaymore wrote:The "best of the best" celadons have a quality of glaze surface and a depth of color that "sings". Knock your socks off. More "average" celadons are nice... but could be "faked" as far as the eye of the non-ceramist is concerned.

Ceramics is a complex field. The correct answer to any question about ceramics is, "It depends". :wink:
lol--like so much in art! Thank you very much for that explanation--that clears up a lot of my confusion about celadon ware. :)

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