Celadon - Application?

[Sheryl Leigh]

Hi all!

 

First off, my apologies if this is in the wrong section.

I'm new to Celadons (are all transparent glazes Celadon?).  I have yet to have a piece where the celadon is a uniform consistency, even on the flat areas (I'm aware that it should be darker for contrast in carving, etc.).  Either drips show up or there is a slight unevenness.  Is this just something you have to deal with in using these glazes or am I missing something in application?  Some of the glazes I'm using are bought, one (Ms. Selsor's faux celadon )was mixed by me.

 

Any help is appreciated!

[neilestrick]

All transparent colored glazes are difficult to apply well. They will show every drip and difference in thickness. It takes some practice to dip well. As the glaze gets thicker it will show variation less, so make sure it's no going on too thin.

[Sheryl Leigh]

Thanks, Neil.  I'm starting to use Specific Gravity measurements when I mix, maybe I'll go a little higher.

[tinbucket]

Adding water + epsom salt or epsom salt alone should help you get a more even application and less drips

[Min]

If the glaze pools it helps hide some of the unevenness of application. Also if you can increase the clay content in the glaze (but not so high as to hinder pooling) so it doesn't drip when you dip that helps too. Spraying works too if you can do that but more time consuming than dipping.

 

[Marcia Selsor]

I spray.

[neilestrick]

I dip.

[Sheryl Leigh]

Thanks for the advice and the examples.  I do have access to a spray booth that I haven't used yet, sounds like this is the time.

 

So, the Epsom salts are a deflocculant, correct?  Is that why it will help even it out?

 

Thank you all again!

[neilestrick]

Thanks for the advice and the examples.  I do have access to a spray booth that I haven't used yet, sounds like this is the time.

 

So, the Epsom salts are a deflocculant, correct?  Is that why it will help even it out?

 

Thank you all again!

 

Epsom salts are a flocculant. It will cause the glaze to gel  bit.

[Sheryl Leigh]

<rolls eyes> Thanks Neil - I'll get this straight sooner or later... *sigh*!

 

[Marcia Selsor]

I don't use epsom salts in these. Here are ^6 Ox faux celadon and ^9 Reduction celadon from my gallery

 

http://community.ceramicartsdaily.org/gallery/image/3541-cone-6-faux-celedon/

Post a photo of your version and compare if it looks the same. It should be the same recipe.

 

http://community.ceramicartsdaily.org/gallery/image/3542-cone-9-celedon-glaze/

 

Both are sprayed.

Marcia (Ms Selsor)

[Min]

<rolls eyes> Thanks Neil - I'll get this straight sooner or later... *sigh*!

 

I was told of an easy way to remember this, just think of a flock of birds. Birds fly together in a "floc" (and get thicker looking) and they fly apart in a "de-floc". So, if you want to gel / thicken up a glaze without decreasing the amount of water in it you add a floc(culant) and if you want to thin it down without adding water you add a defloc(culant). 

[MatthewV]

are all transparent glazes Celadon?

> No, technically Celadon glazes are low-iron glazes which turn green to blue in reduction at high temperatures. But today the word seems to be "any lightly colored mostly transparent glaze".

 

Anyways, fake Celadon glazes still have wonderful texture enhancing qualities that generally sensitive to the thickness of glaze application. Especially on horizontal pieces.

[flowerdry]

See if you can find Pete Pinnel's essay on flocculation vs deflocculation. That was what finally made things click for me. If you think of it in terms of thick vs thin you will eventually become confused because that is not what it going on.

[Min]

See if you can find Pete Pinnel's essay on flocculation vs deflocculation. That was what finally made things click for me. If you think of it in terms of thick vs thin you will eventually become confused because that is not what it going on.

 

http://www.claytimes.com/articles/glazeadjusting.html Pinnell article covering flocculation and deflocculation.

 

Absolutely agree, thick and thin are just descriptive terms of what the glaze looks like with flocs and deflocs.

[preeta]

Matthew thank you for answering the question i was going to ask. i know celadon traditionally. Even though Chinese in origin the word is French i believe. And i also came across many shades of faux ^6 celadons from Amaco i believe?

 

Sheryl what cone do you fire to? gas? electric? reduction? do you mix your own glazes? or get dried glaze mixture? or straight from the bottle? do you dip or brush on?

 

and now more questions:

 

is there a colour difference between ^6 and ^10 or more? (i have read the article on RIO colours on CAD - how the % and temp. matter, my point with this question is can you kinda achieve in ^6R close to what you can achieve in ^10R?) or does that depend on the other ingredients. for instance RIO with neph. syn. or RIO with Custer feld. do the oxides that change colour change at a particular temperature in reduction? would a rutile in ^10 be different than ^6. what if its on the glaze as an oxide drawing? would rutile appear say orange in ^6R but green in ^10R (just using random colour references to ask the question here).

 

off topic - i know copper reds are hard to achieve. with the right recipe can i get a copper red (some form of copper red) in ^6 if i fire the way copper needs to. 

 

Sheryl thank you for asking this question. i had no idea there is a difference in application between opaque and transparent glazes. i learnt so much from this thread. 

[Fred Sweet]

Presets-

You are correct in that celadon is a French word and not Chinese. A little research gives the origin of the French word as: "mid 18th century: from French céladon, a color named after the hero in d'Urfé's pastoral romance L'Astrée (1607–27)."

A little off topic, but I thought you might enjoy a little history to the term.

[Sheryl Leigh]

Have I mentioned how wonderful you all are?  I love the discussion a question engendered ... techniques to chemistry to historical language.  This is what draws me to the ceramic community.

 

Preeta, to your questions - 

 

The celadon and transparents I have been using have been the full range - I mixed Ms. Selsor's ( ) Faux ^6 Celadon from raw materials.  I have a Laguna dry ingredient mix called "Peacock", the 'stiffer' version.  And I have Amaco's ^5/6 Celadons as well.  I get the evenest coverage from the Amaco glaze, but haven't found their prices attractive. I also prefer to be able to tweak recipes - I only wandered into the pre-bought stuff so other studio members would have something to use while I figure this stuff out.

 

For my ^6 firings, I use an electric Skutt on a slow ramp program with no hold and natural cooling to ambient temp.  Oxidation assumed.

I wish I could answer your other questions, but from their content I can tell that you already know more about them than I do, lol.  I'm sure there is a bunch of people here that can answer you - my only suggestion is to take a look at John Britt's Mid-Range Glazes.  He has a group of 9 ^5/6 copper reds, but notes that they still need a reduction atmosphere or they will turn blue.  Not a horrible trade-off, but.....   He also has Chrome/Tin and Artificial Copper (SiC) reds.  Hope this is helpful.

[neilestrick]

A true celadon will only get its color from iron, which means it needs to be fired in reduction, typically at cone 10. The color can range from grey to blue to green. When fired in oxidation, those glazes tend to go yellow. A cone 5/6 oxidation celadon will be a 'fake' celadon, and will have to get its color from copper or a stain. Cone 6 celadons can have the same surface qualities and behave the same as the cone 10 glazes, and be every bit as beautiful. I recently formulated a cone 6 'celadon' that has the same qualities as the  cone 10 reduction celadon I used to use, but it's more consistent. The Amaco celadon line are beautiful glazes, with the same softness and depth as true celadons, but in a wide variety of colors.

[oldlady]

neil, just came across this while searching out marcia's recipe for faux celadon.  a link to that is posted above.    would you be willing to share your recipe?   thank you

[yappystudent]

A timely thread as I just invested in four pints of Amaco ^6 celadon-like glazes because they supposedly can be mixed and here's the results. I brushed 3 coats, except for the flat rounded dishes where I deliberately added more glaze to the center. IMO they performed pretty well despite overly groggy clay, they'd look better on porcelain. 

BTW the number on the green I mixed is my own code it not the manufacturer's. 

[oldlady]

yappy, how did you manage to make my pots?   i  am doing the same colors on almost the same shapes this week.  there really is nothing new in ceramics.   well, i do not have holes in the centers but otherwise we are doing very similar things.   glad you found nice, transparent colors that you like.

my glaze is made from ingredients that all look like white powder except when i add the mason stains.    i have about a hundred to go to fill the basket of small things that i sell all summer.   thankfully, min has helped me figure out a great base glaze that will take colors well. hooray for Min!    

I WOULD NEVER CALL THEM CELADONS,  that is just wrong.   they are transparent colors.  amaco is just using a name for marketing purposes.  using it cheapens and trivializes the enormous amount of very hard work done over centuries to make true celadon glazed pots.  i can rant all i like, it will not change anything.   enjoy your colors and pots.

(what are the holes for, incense?)

[Dick White]

Alice, I will refrain from getting you started on the commercial "celadons" if you will excuse me for starting a similar rant about the line of "shinos" from that other commercial purveyor...

[yappystudent]

If the shoe fits IMO. If there 's an easier path to things I'm usually trying to be on it. And I said celadon-like. I love real celadon but please, these aren't the middle ages. *ducks* 

@Oldlady: For one thing your work is much better than mine so I'm sure they look nothing alike, but, you make pipe knocker ashtray-incense burners too? 

[Callie Beller Diesel]

I think we get fruatrated with the inaccurate naming of things because it makes some definitions too broad over time, and especially for our particular Internet teaching purposes, that can make our jobs harder.   @yappystudent To extend your metaphor, stating the shoe fits is like my six year old trying to tell me her sandals still fit from last year, even though her toes are hanging off the edge. It misses certain key facts that are going to become painfully important to the user. 

If someone says "I'm having trouble with this celadon," those of us answering questions have to first establish the frame of the asker's reference so that we can solve the right problem. Are they in a community studio or self taught, and are therefore asking about the brushability of a bottled glaze, or are they an undergrad student working at cone ten reduction, mistakenly trying to use porcelain and red iron oxide to achieve that exact Koryo Dynasty shade? Even though the store bought and the home-mix might be (sort of) the same colour and translucent, they're two different animals with wildly different sets of problems. 

Edited to add: the end results of both categories are lovely and are classics for good reason. It's just the wrong nomenclature that becomes vexing.