Blue Celadon Glazes

All of the following Blue Celadon recipes and more can now be found on my new open-source ceramics recipes website, Glazy: https://glazy.org/search?base_type=460&type=510&cone=high

Complete Guide to High-Fire Glazes

These are tests of some of the Blue Celadon Recipes found in High Fire Glazes.  Tests fired in multiple kilns in temperatures ranging from 1300-1310 Celsius reduction.

Craig Martell Blue Celadon

Custer Feldspar:  61.7, Silica: 21.2, Barium Carbonate: 4.5, Wollastonite: 12.7, Black Iron Oxide: 1

Pete Pinnell Blue Celadon

Custer Feldspar:  24.5, Silica: 34.3, Whiting: 19.6, Kaolin (Grolleg): 19.6, Barium Carbonate: 1.9, Tin Oxide: 1, Yellow Iron Oxide: 0.5

Sam’s Satin

Custer Feldspar:  40, Silica: 34.5, Whiting: 15.5, Barium Carbonate: 4, Dolomite: 6, Yellow Iron Oxide: 0.5

Cliff Lee Blue Celadon

Custer Feldspar:  50.5, Silica: 24.9, Whiting: 17.2, Kaolin (Grolleg): 3.7, Dolomite: 2.6, Zinc Oxide: 1.1, Red Iron Oxide: 0.75

Choy Blue

Custer Feldspar:  50, Silica: 28, Whiting: 6, Kaolin (Grolleg): 4, Barium Carbonate: 12, Red Iron Oxide: 2

Ishii Blue Celadon

Custer Feldspar: 49, Silica: 31, Whiting: 20, Black Iron Oxide: 1

Celadon Blues

Robert Tichane’s Celadon Blues focuses primarily on Chun (Jun) glaze, but also covers QingbaiLongquan, and other ancient Chinese glazes.  While perhaps not as informed as Nigel Wood’s Chinese Glazes, Tichane approaches the subject from the perspective of a glaze chemist and gains valuable insight into the nature of blue celadons.  Through testing, Tichane arrives at two formulas.  The “532.1” formula contains 50 parts feldspar, 30 parts silica, 20 parts limestone, and 1 part iron oxide.  The “5321.1” formula is the same but adds 10 parts kaolin.  The type of kaolin added greatly affects the color of the glaze, for blue celadons a kaolin very low in titania such as Grolleg or New Zealand Halloysite is required.

Below on the left is Tichane’s 532.1 formula with 1% yellow iron oxide (YIO).  On the right is the same formula but with Wollastonite instead of Whiting (of course this adds some silica to the mix).  These tests were fired in a public kiln, temperature is uncertain but at least Orton cone 12, I believe Tichane’s tests were fired to cone 10.

It is quite simple to create a blue celadon suited to your particular firing style using Tichane’s methods and triaxial blends.  From a triaxial blend of potash feldspar, silica, and whiting I arrived at a recipe suitable for Orton cone 11-12 reduction firings:  56 feldspar, 30 silica, 14 whiting plus .6-.8 yellow iron oxide.  Some variants of this glaze are shown below.  All tests fired to approximately Orton cone 12 in heavy reduction.

Formulating Your Own Celadon

Personally, I really like the Pinnell Blue Celadon recipe in John Britt’s book.  It’s a very beautiful, smooth and “natural-looking” blue celadon.  However, I’ve found that the glaze is difficult to apply given the large amount of Kaolin in the recipe.  A few months ago I fired about 20 pieces with Pinnell celadon with beautiful results except that the glaze crawled on every single pot.  I still haven’t determined if the problem was due to a) glaze application (sprayed inside, dried, then sprayed outside), b) ball milling the glaze for too long (3 1/2 hours), or c) too much shrinkage of the glaze due to the kaolin (using New Zealand Halloysite).

And although no-kaolin recipes like Tichane’s 532.1 and Craig Martell’s blue celadon almost always fire a nice blue, they seem a little artificial to my tastes, perhaps a little too colorful.  It’s also because this type of Wollastonite-based celadon is covering a lot of Jingdezhen ware these days, and I’m tired of seeing it.  Finally, these glazes tend to sink to the bottom of glaze buckets and solidify there due to lack of clay.

So I decided to do a simple triaxial, based in part on Tichane’s 5321.1 recipe.  I still want kaolin in the recipe, but not as much as in Pinnell blue celadon, so I picked an amount halfway in-between the two, 10%.  (Again, I’m using New Zealand Halloysite.  Grolleg is also suitable.)  I also decided to add 3% dolomite- based on Nigel Wood’s Chinese Glazes and past experience I know that a little magnesium combined with the calcium can give the surface a slightly waxy feel.  With 13% of the recipe taken up by kaolin and dolomite, I have to adjust 87% Potash Feldspar, Silica, and Wollastonite.  (You could use Whiting of course, although it out-gasses more than Wollastonite.)  Finally, I’m not adding any Barium Carbonate.  (If you want a rich blue celadon you can try adding 2-4% Barium Carbonate.)

All these tests are the same porcelain body fired together in a heavy reduction atmosphere to Orton cone 10 1/2.

I realize it’s really difficult to see the differences between glazes in such a small photo.  Furthermore, some tests look richer, but it’s partly due to small changes in camera exposure and glaze thickness rather than glaze composition.  I prefer the diagonal lines going down with Wollastonite at 20-22 percent.  I should have added another couple rows to the bottom of the triaxial, because I prefer the glazes more as the silica increases.  (I thought there was already too much silica in the glaze, including silica contributed by the wollastonite, so I stopped early.)

Below is a bigger photo of one of the tiles.  It’s almost like some Longquan glazes I have seen.  I think this particular glaze would look great over carving or molded/sculpted work, and it might really look good on stoneware or dirty porcelain.  I’ll post pictures once I try it out.

I’ve posted the recipe on Glazy:  http://glazy.org/recipes/3189

Adjusting Pete Pinnell’s Blue Celadon

Years ago I tested Pete Pinnell’s Blue Celadon recipe and loved it, so much so that I didn’t even think of bothering to adjust the original recipe to suit my materials.  But this last kiln I wanted to try swapping out Whiting for Wollastonite, and I thought I might as well adjust for New Zealand Halloysite instead of Grolleg.

Below is a small triaxial of Pinnell’s Blue Celadon adjusted for New Zealand Halloysite.  The top of the triaxial is the closest verison to the original.

Using Halloysite instead of Grolleg wasn’t a huge change, and I couldn’t see much of a difference from the original recipe.  The bottom of the triaxial is somewhat interesting- color improves as silica replaces halloysite.  This is a similar finding as with Tichane.

Replacing Whiting with Wollastonite

Next is Pinnell’s Blue Celadon with New Zealand Halloysite instead of Grolleg, and Wollastonite instead of Whiting.

The recipe at the top of the triaxial most closely matches the original recipe.  As with the previous triaxial, color is better on the right side where silica is greatest.

As with many wollastonite-based celadon glazes, this glaze has a very fine network of bubbles that are smaller and more evenly sized than those in the whiting recipe.

It is difficult to see in the photograph, but the color is also better in the wollastonite version.  I believe this is due in part to the fact that much of the silica is introduced with the wollastonite.

My favorite glaze is the Halloysite/Wollastonite recipe at the top of this triaxial (which is closest to the original recipe).  You can find it on Glazy: http://glazy.org/recipes/4571

However, I also like the glaze on the right of the second row.  I wish I’d done a test to the right of the top glaze, in other words Potash 30.5, NZ Kaolin 18.5, Silica 24.

Pinnell’s Blue Celadon with Halloysite and Wollastonite.

Blue Glazes

All of the following Blue glaze recipes and more can now be found on my new open-source ceramics recipes website, Glazy: https://glazy.org/search?base_type=460&type=750&cone=high

The following tests were fired in two Jingdezhen public kilns at approximately cone 12 and in my own kiln at cone 10.  I just wanted to get a general idea of the blue glazes listed in High Fire Glazes.

Market Blue

Custer Feldspar 50, Whiting 4, Kaolin 24, Dolomite 22, Cobalt Carbonate 0.5

Royal Blue

Custer Feldspar 27.3, Whiting 23.3, Silica 27.3, Kaolin 19.2, Zinc Oxide 3, Cobalt Carbonate 5

Satin Sky

Winn Blue

Blue 1

Dark Water Blue

This recipe calls for 2% additional Iron Chromate, which I don’t have.  I tried this glaze without the Iron Chromate, as well as substituting Iron Chromate for a combination of Red Iron Oxide and Chrome Oxide.  I don’t know what this glaze is supposed to look like..

Blue 4

This recipe calls for 13% additional Ultrox, which I don’t have.  I tried substituting with Zircopax, the result is kind of strange.

Porcelain Stone Glazes

Jingdezhen Porcelain Stone

There are a number of types of porcelain stone mined throughout Jingdezhen and the surrounding countryside.  Some are more suitable for making porcelain clay, while others are traditionally used for glazes.  It is difficult to know how similar modern-day porcelain stone is to traditional materials.  During the few years I have lived in Jingdezhen, some mines have been closed off to private mining, while others have simply run out of material.  Those still operating often mix poor-quality material with good material in order to increase production.  And plaster is added in ever increasing amounts in order to make the porcelain stone bricks less likely to break in transit.

Below are three types of porcelain stone fired to 1310 Celsius in a reduction atmosphere.  From left to right:  San Bao porcelain stone, Yaoli glaze stone #1, Yaoli glaze stone #2.

Most porcelain stone is made from a combination of rocks.  The stones below are used to make Yaoli glaze stone.  On the left is the more common, dirtier stone, in the middle is the higher quality stone, while the right is the mixed, washed and purified stone before adding plaster.  All examples were fired to 1310 Celsius in reduction atmosphere.

San Bao Porcelain Stone (三宝瓷石)

Below are some simple tests of porcelain stone from San Bao Village (三宝瓷石).  This stone is often used for making traditional porcelain clay, but it can also be used for glazes.  (However, usually “glaze stone”, or 釉果, is used for glazes.)

The only chemical analysis I have found for San Bao Porcelain Stone comes from 陶瓷艺术釉工艺学 published by 江西高校出版社:

SiO2: 7.013, Al2O3: 17.64, Fe2O3: 0.69, CaO: 0.54, MgO: 0.09, K20: 4.02, Na2O: 4.68.  LOI 2.01

(The SiO2 amount is most likely a typo, they probably intended to write 70.13.)

However, this analysis can only be used as a basic guideline.  There are noticeable differences between the porcelain stone produced by various families in San Bao, and quality seems to change every year.

Traditional glaze recipes usually call for whiting, but unless fired very carefully, porcelain stone has a tendency to carbon-trap when whiting is the flux.  Replacing whiting with wollastonite eliminates this problem.

Below are a few glazes containing San Bao porcelain stone, silica, wollastonite and kaolin.  It is quite easy to make a very nice celadon with porcelain stone.

Yaoli Glaze Stone (瑶里釉果)

Yaoli Glaze Stone (瑶里釉果) is traditionally used for creating glazes.  As with San Bao porcelain stone, there are a number of families mining, cleaning, and creating the glaze stone bricks sold in Jingdezhen.

陶瓷艺术釉工艺学 has the following analysis:

SiO2: 73.99, Al2O3: 15.55, Fe2O3: 0.37, CaO: 1.76, MgO: 0.33, K20: 2.88, Na2O: 2.63.  LOI 2.88

But again, the material varies from seller to seller and from year to year.

At the left is a simple melt test of 75% glaze stone with 25% Wollastonite and 80% glaze stone with 20% Wollastonite.  The 20% Wollastonite version is already a perfectly useable celadon.

Below are a few simple celadons made with glaze stone, silica, wollastonite, and kaolin.

Porcelain Bodies

80% Porcelain Stone, 20% Kaolin

A test of 80% porcelain stone and 20% kaolin (New Zealand halloysite).  This porcelain is particularly white and fairly translucent.  It is quite nice to throw but fragile when bone dry.  Mixtures of various types of porcelain stone with between 10-40% kaolin produce porcelain bodies suitable for a range of temperatures.

Black Glazes

All of the following black glaze recipes and more can now be found on my new open-source ceramics recipes website, Glazy: https://glazy.org/search?base_type=460&type=880&cone=high

Here are a few black glazes, mostly from John Britt’s book High Fire Glazes.

Val’s Satin Black

From Val Cushing.

  • Custer Feldspar: 20
  • Soda Feldspar: 20
  • Whiting: 2
  • Silica: 20
  • Ball Clay: 10
  • Talc: 13
  • Dolomite: 15
  • Add: Red Iron Oxide: 3
  • Add: Manganese Dioxide: 2
  • Add: Cobalt Oxide: 3
  • Add: Chrome Oxide: 1

Val’s Satin Black Variation

From Ceramic Arts Daily:

  • Custer Feldspar: 20
  • Soda Feldspar: 20
  • Whiting: 2
  • Silica: 20
  • Ball Clay: 10
  • Talc: 13
  • Dolomite: 15
  • Add: Red Iron Oxide: 9
  • Add: Cobalt Carbonate: 3

Fat Black

From The Complete Guide to High-Fire Glazes:

  • Custer Feldspar: 32.7
  • Whiting: 15.4
  • Silica: 32.7
  • Kaolin: 9.6
  • Ball Clay: 9.6
  • Add: Red Iron Oxide: 8
  • Add: Cobalt Carbonate: 3.8
  • Add: Bentonite: 2

Kaki (Persimmon, Tomato) Glaze

Here are a few Kaki glazes, mostly from John Britt’s book High Fire Glazes.  You can find these recipes (with updated cone 9 & 10 photos)  and more on my glaze website Glazy: https://glazy.org/search?base_type=460&type=570&cone=high

Coleman Kaki

Custer Feldspar 48, Silica 16, Whiting 9, Kaolin 7, Talc 9, Bone Ash 11, Red Iron Oxide 11.5

KC Red Kaki

Custer Feldspar 45.7, Silica 24.5, Whiting 6.4, Kaolin 6.4, Magnesium Carbonate 6.4, Bone Ash 10.6, Red Iron Oxide 6.4

Anderson Ranch Kaki

Custer Feldspar 45, Silica 20, Whiting 7, Kaolin 8, Talc 8, Bone Ash 12, Red Iron Oxide 13.5

Staley’s Kaki

Custer Feldspar 48, Silica 26, Kaolin 7, Magnesium Carbonate 7, Bone Ash 12, Red Iron Oxide 8

Kaki

Custer Feldspar 30, Silica 20, Kaolin 20, Dolomite 15, Bone Ash 15, Red Iron Oxide 10

Val’s Tomato Red

F-4 Feldspar 45, Silica 24, Whiting 7, Kaolin 7, Magnesium Carbonate 6, Bone Ash 11, Red Iron Oxide 8

Chinese Glazes Russet Ding

Left:  Potash Feldspar 26, Silica 25.5, Kaolin 34.5, Dolomite 10, Titanium Dioxide 1, Red Iron Oxide 10

Right:  Potash Feldspar 30.5, Silica 30, Kaolin 28.5, Dolomite 7, Titanium Dioxide 1, Red Iron Oxide 5.5

Tianmu (Temmoku) Glazes

Here are a few Tenmoku glazes, mostly from John Britt’s book High Fire Glazes.  You can find these recipes and more on my glaze website Glazy: https://glazy.org/search?base_type=460&type=540&cone=high

Hamada Temmoku

Custer Feldspar 50, Silica 30, Whiting 20, Red Iron Oxide 9

Leach Temmoku

Custer Feldspar 40, Silica 30, Whiting 20, Kaolin 10, Red Iron Oxide 9

Rust Black

Custer Feldspar 46.2, Silica 23.2, Whiting 17.4, Kaolin 10.9, Zinc Oxide 2.3, Yellow Iron Oxide 11.2

Jeff’s Temmoku

Custer Feldspar 53.8, Silica 22.4, Whiting 12.9, Kaolin 6, Barium Carbonate 2.5, Zinc Oxide 2.5, Red Iron Oxide 8.9

Secrest Temmoku

Custer Feldspar 53, Silica 24, Whiting 12, Kaolin 6, Barium Carbonate 2.5, Zinc Oxide 2.5, Red Iron Oxide 10

Mark’s Temmoku

Custer Feldspar 45, Silica 27, Whiting 17, Kaolin 11, Red Iron Oxide 10

Johnston Temmoku

Custer Feldspar 59.1, Silica 23.4, Whiting 12.7, Kaolin 4.9, Red Iron Oxide 7.7

Roy Temmoku

Custer Feldspar 58.7, Silica 21.7, Whiting 12.4, Bell Dark Ball Clay (sub regular Ball Clay) 7.2, Red Iron Oxide 7.7

Natural Quarts and Mica additions to porcelain

Test of adding natural quartz and mica to porcelain.

Porcelain is Taida 609 fired to 1310 celsius in reduction.

Top row: 5, 10, 15, 20% addition of silica to 100g porcelain slip
Bottom row: 5, 10, 15, 20% addition of mica to 100g porcelain slip

IMG_6430

The natural quartz has a ton of impurities. Also I did not consistently grind or filter the quartz. Addition of quartz impedes translucency.

IMG_6436

I’m not sure exactly what type of mica I used. However, it seems pretty clean and of uniform particle size. Didn’t notice translucency affected much. The last tile is a little thicker than the others so appears more opaque.

IMG_6438