Jump to content

Black Pottery Without Terra Sigillata?


Recommended Posts

Hi all,

 

First post. I'm searching for some insight into black firing. Let me preface by saying I have been using a really simple black firing technique for about 5 years with great results. It involves wrapping a polished terra sigillata pot (that has been bisqued at ^010) in newspaper and then sealing everything up in an aluminum foil "pouch". The piece is fired at ^021 in an electric kiln, which is just hot enough to burn up the newspaper but not damage the foil. The newspaper carbonizes and leaves the pot with a jet black color. I use 04-06 white earthenware and a white commercial terra sig.

 

I'd like to achieve the same smoke black color in my ware but without the use of terra sigillata or even burnishing. I have seen many pieces of black pottery that are not polished/burnished and I'm wondering if anyone can tell me how this is done? I have tried using the aforementioned technique on non-terra sig/non-burnished pots but all it does is give the pot a "dirty" look, like someone burried it in dirt and dug it back up.

 

Any help is appreciated!

 

Spencer

 

 

Link to comment
Share on other sites

Hi Spencer,

Here is a little black pot I did about three years ago. I don't know if it's black enough for you, or if it has the "dirty" color that you refer to, but it was easy to do.

I just fired it in my raku kiln to about 1600 F, then pulled it and did a hard reduction in a can with newspaper.

It is a cone 6 white stoneware, bisqued to 04, not burnished or anything. You can see some of the newspaper marks on it from the reduction, but they are a little more apparent in the pic than in person. I just did it to see what would happen, and it turned out pretty well for me.

gallery_5042_241_183151.jpg

Link to comment
Share on other sites

Thanks a lot, Madison. Your piece is beautiful. I would actually be very interested in achieving something close to that. I suppose I could go the raku route, but I've never done that so I'll need to read up on it. I may not have made myself clear, but I am NOT looking for the dirty look that I got when I tried getting a black color in my electric kiln without the terra sigillata. I only got satisfactory results with the terra sig.

Link to comment
Share on other sites

No, your post was clear, I understand that you don't want the dirty black look. I was just hoping that MY pot didn't have that dirty look, and wouldn't be any help.

We use our electric kiln for raku some, and you could either do that also, or, what I have also done is a technique similar to yours. After we are done "rakuing" with the electric kiln, it is still hot of course. I was bothered by that waste of heat, so I began wrapping little pendants and pots in foil with combustibles, like you do. Then I would put them into the still-hot kiln, and as it cooled, the paper and such would burn up as you described. The pieces came out nice and black, but they had been burnished; I didn't use a terra sig, I just burnish the grogless white stoneware, and it gets surprisingly smooth.

Anyway, somebody can help, there are some really helpful people here!

Link to comment
Share on other sites

post-5885-13027347856217_thumb.jpgSpencer, I do blackware in my electric kiln also, bisque fired to cone 08, and finish fired to cone 018. I place the piece in an unventilated tin canister, such as a popcorn tin (I stock up at garage sales in the summer and Christmas). Put a bunch of sawdust, paper, and such, and fire the kiln. This is definitely something for outdoor or garage kiln. My kilns are in my garage and I fill it with smoke every time. You may need to vary the type and amount of combustibles to get the look you are going for, I end up adjusting at least once a year depending on the wood projects i'm doing. i use only about and inch or so of sawdust and few sheets of paper.

 

I mainly use terra sig, but it has produced nice even blacks on the unsig'd area. below is a photo or recent piece that sig was only on the foot and rim.

 

Hope that helps.

Chad

post-5885-13027347856217_thumb.jpg

Link to comment
Share on other sites

Guest alabamapotter

Hey,

You don't have to put terra sig on if you're going to turn it black.... The terra sig is mostly for the white on Red pottery, not the black on black.

The great thing about the black pottery is that if you don't like the results, it burns back off between 700 and 800 degrees and deposits

between 500 and 600 degrees (ball park figures since combustibles burn at 451 degrees.). Black pottery is blacker the shinnier it is....

And becomes shinnier ( is that even a word?) if you use alittle Turtle wax afterwards on a burnished pot. I've experimented wedging oil directly into the clay.... and it works.... or you can brush on oil, then burnish, fire and cover with DRY combustibles.... horse/cow manure, oak leaves, grass. etc.

but don't let that stuff burn off.

I may not be the best person to respond to your question since I never bisque my stuff first but I thought I'd give some insights on

experimental black pottery from the early 1990's.

Good luck.

Alabama Potter.

Link to comment
Share on other sites

Hi all,

 

First post. I'm searching for some insight into black firing. Let me preface by saying I have been using a really simple black firing technique for about 5 years with great results. It involves wrapping a polished terra sigillata pot (that has been bisqued at ^010) in newspaper and then sealing everything up in an aluminum foil "pouch". The piece is fired at ^021 in an electric kiln, which is just hot enough to burn up the newspaper but not damage the foil. The newspaper carbonizes and leaves the pot with a jet black color. I use 04-06 white earthenware and a white commercial terra sig.

 

I'd like to achieve the same smoke black color in my ware but without the use of terra sigillata or even burnishing. I have seen many pieces of black pottery that are not polished/burnished and I'm wondering if anyone can tell me how this is done? I have tried using the aforementioned technique on non-terra sig/non-burnished pots but all it does is give the pot a "dirty" look, like someone burried it in dirt and dug it back up.

 

Any help is appreciated!

 

Spencer

 

 

 

 

I get coal-black pots (with no terra sig or brunishing) at cone 6 simply by firing them in an electric kiln in saggers filled with used coffee grounds.

Link to comment
Share on other sites

I have recently bought professional smooth black clay for a scuplture project and have test fired it to both ends of the 1080 to 1270 degrees C firing range .... the higher the temperature, the blacker the result, (even the lower temp resulted in quite a nice warm brown/black) and I'm fairly confident it will give me the silky-black result I want. I don't know of the availability of such clays in America - but I'm sure they're out there.

 

 

Link to comment
Share on other sites

  • 2 weeks later...

I've pit fired and did some saggar firing recently using the mummy technique. The right carbon combustable will give you black but the looser the wrap or enclosure you have it in the more fumes will escape away from your pot. Build a nice tight saggar box foe your nex firing and your blacks should be deeper.

Link to comment
Share on other sites

When I fire my raku kiln (propane fuel) to approx cone 06, my post-firing reduction is done on a bed of sawdust covered with 4 to 6 pages of newspaper that curl around the pot when it's set down and then covered with another 2 to 3 pages of newspaper. As long as the newspaper is the combustible closest to the pot I end up with a velvety black. After about 8 minutes, I lift the lid of the smoke pot, and as the combustibles re-ignite, add another page or two of newspaper. Close the pot down and leave it until the next batch is ready to come out of the kiln. I immediately quench in a bucket of water. I only burnish when I want the difference in the blacks--shiny or matte.

Link to comment
Share on other sites

Hi all,

 

First post. I'm searching for some insight into black firing. Let me preface by saying I have been using a really simple black firing technique for about 5 years with great results. It involves wrapping a polished terra sigillata pot (that has been bisqued at ^010) in newspaper and then sealing everything up in an aluminum foil "pouch". The piece is fired at ^021 in an electric kiln, which is just hot enough to burn up the newspaper but not damage the foil. The newspaper carbonizes and leaves the pot with a jet black color. I use 04-06 white earthenware and a white commercial terra sig.

 

I'd like to achieve the same smoke black color in my ware but without the use of terra sigillata or even burnishing. I have seen many pieces of black pottery that are not polished/burnished and I'm wondering if anyone can tell me how this is done? I have tried using the aforementioned technique on non-terra sig/non-burnished pots but all it does is give the pot a "dirty" look, like someone burried it in dirt and dug it back up.

 

Any help is appreciated!

 

Spencer

 

 

 

 

I get coal-black pots (with no terra sig or brunishing) at cone 6 simply by firing them in an electric kiln in saggers filled with used coffee grounds.

 

 

I have also noticed nice blacks with coffee grounds. I've also heard cow patties can give some nice blacks.

Link to comment
Share on other sites

Cow pies work well for covering pit firings. For saggars, a horse turd is much richer in nitrogen and can even give a black iridescence to the surface.

(I lived in Montana for 31 years with easy access to such material!)

Marcia

 

 

Nice! I'll keep that in mind. I've been pit firing but I want to play around with saggars more.

Link to comment
Share on other sites

Hi all,

 

First post. I'm searching for some insight into black firing. Let me preface by saying I have been using a really simple black firing technique for about 5 years with great results. It involves wrapping a polished terra sigillata pot (that has been bisqued at ^010) in newspaper and then sealing everything up in an aluminum foil "pouch". The piece is fired at ^021 in an electric kiln, which is just hot enough to burn up the newspaper but not damage the foil. The newspaper carbonizes and leaves the pot with a jet black color. I use 04-06 white earthenware and a white commercial terra sig.

 

I'd like to achieve the same smoke black color in my ware but without the use of terra sigillata or even burnishing. I have seen many pieces of black pottery that are not polished/burnished and I'm wondering if anyone can tell me how this is done? I have tried using the aforementioned technique on non-terra sig/non-burnished pots but all it does is give the pot a "dirty" look, like someone burried it in dirt and dug it back up.

 

Any help is appreciated!

 

Spencer

 

 

 

 

 

 

Hello Spencer

If you research the works of Philip Cornelius and Byron Temple you may find an answer to your question. Both of the ceramists at different times used charcoal in high temperature firings to achieve extremely black colours on unglazed clay. At the workshop I attended with Byron Temple, charcoal briquettes were placed in a saggar together with the pots.

 

John Leach, UK, (http://www.johnleachpottery.co.uk/john-leach-signed-pots.asp) uses sawdust in saggers with the pots. He manipulates the saggars (cracks in certain places to let in oxygen) and the levels of the sawdust to create spontaneous painterly definitions. I have achieved lustrous ebony blacks at Cone10 in raw(once) firings in a salt kiln using only the residual salt from the walls, shelves etc (no salt was added to those firings as I was extending the life of the kiln by vapourizing the residual salt off the walls). I think that the addition of a small amount of salt with the charcoal might get the same lustrous surface.

 

All of these techniques are high fired.

Johanna

Link to comment
Share on other sites

I have fired blackware that had terra sig applied, burnished and bisque fired prior to the blackware firing. So, seeing this post I was intrigued to see if I could reproduce a similar black by not following my usual method, and I had a piece of bisqueware to use. So here is what I do & did:

 

I get rich blacks from terra sig, so I sprayed some onto my bisqueware pot, but did not burnish at all, or fire the terra sig on. Wrap the pot in low grade toilet tissue such that there are 5 or 6 layers all around the pot; top, sides and bottom. Wrap the tissue covered pot in a heavy duty aluminum foil, using butcher wrap technique to assure the most airtight seal. Place the foil wrapped pot in your kiln and fire to 1200 degrees Fahrenheit, watching for foil breakdown and smoking that may indicate the foil has broken down and oxidation could occur (I noted on the pot in the attached picture that I had a possible breakdwon near the bottom of the foil package.) Let the foil package cool and unwrap. I also waxed the pot with some paste wax for a little shine.

 

Most of the pot is a deep uniform black. One can see an area where the color is more a deep brown, and I am assuming this is where the foil let in air. Perhaps if I had fired at a lower peak temperature the foil would have remained intact and the black uniform all over. The toilet tissue was intact for the most part, but had turned into a flat black carbon.

 

John L.

post-2045-13046170356739_thumb.jpg

post-2045-13046170356739_thumb.jpg

Link to comment
Share on other sites

Hello Spencer

My apologies for not reading your initial email properly. I realize that I ignored the fact that you are using a cone 06-04 earthenware clay. I have attached a small .pdf of some earthenware black fired pots that was taken in the Black Pot factory just outside Taiyuan in Northern China. Whilst there I observed that the kilns were COAL fired in extremely heavy reduction. From the slag build up around the firebox/doorway of the kiln I would hazard a guess and say there would be some salt floating around as well. I have included the images of the kiln and the slag that is pulled out of the firebox.

 

The pots were burnished but no Terra Sig. In the image of the pots you can see the difference between the burnished and non burnished background of the carving. All the pots there were jet black. The briquettes in the sagger plus a small amount of salt should still work at the temperatures you are working at. It is worth a try.

 

Johanna

Black fired ware, Taiyuan, Northern China.pdf

Black fired ware, Taiyuan, Northern China.pdf

Link to comment
Share on other sites

  • 2 months later...

Hi Spencer,

I was just looking at a you tube for Hildegard Anstice. She has 5 DVDs and one is on black firing technique. It looks like it involves pouring something (probably liwuid sugar) into a primitive gas kiln. You may be interested in checking it out. Will keep watching this forum to see how you go. good luck!

Jan

Link to comment
Share on other sites

  • 10 months later...

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.