Yet Here’s a Spot.

(Hark! he speaks!)

An oil spot, naturally. Those glazes are somewhat of an obsession for me and the reason I fire my electric kiln to cone 9-9.75 and not to cone 6 like more sane people.

Here’s something I made in France:

Image

It’s black, the gold is just the sun reflecting off the spots. Still pretty decent… and my first one. Little did I know how lucky I was to get this. This is what I thought was a common oil spot recipe called Candace Black. Of course I had to translate it to available materials, and some things got mangled in translation.

Here’s something I fired just a week ago, from a batch of bona fide North American material Candace Black:

Image

The spots are numerous and delicate – quite different from the big distinct spots I got in France.

Aha, says the knowledgeable potter. The spots become bigger if you apply the glaze thicker. And they do:

Image

Up to a point. Beyond which, disaster strikes:

Image

The spots grow until they have nowhere else to go and then they lose the black background and just coalesce to a continuous metallic surface. And worse, they start to form unhealed bubbles.

Skip two months of painstaking testing, re testing, and reformulation… I think I’m getting somewhere:

Image

And taking another line of research, also this:

Image

Of course, these are small bowls that I made for testing glazes on… A different story from my 1.5 foot bowls that I’ve been dreading to glaze with a glaze that I’m not 100% sure about. We’ll see how it goes.

And while on the subject of bowls. Look what I’ve made!

Image

Big, celadon, spiral(!)

I usually make my bowls ‘perfect’. This has caused me some aggravation since I believe the first duty of a functional pot is to function. A bowl needs to be smooth on the inside – so that if you use a spoon on it, it won’t grate. But I’ve been trying to push my boundaries. Leave the bottom smooth and push the ripple through the sides.

Image

The spots were a surprise. Usually you get them if you don’t sieve the celadon well enough. I, however, put them there on purpose by wedging granular iron into my pristine porcelain… Not sure I’ll repeat the experiment although people inform me that it looks just like a robin’s egg.

There is actually a whole set of them – I made them to nest. But my bowls seem not to be team players – they are pots in their own right – really hard to get a multiple pot object to look good both individually and assembled. I’ll file the nesting bowl project under ‘needs more work’ and go back to admiring my celadon spiral.

 

 

Return of the prodigal potter

Where have I been?Potting obviously. Mostly immersed in glaze development for cone 10 oxidation. But in the mean time I set up my etsy store and even made my first sales! Check it out at https://www.etsy.com/shop/PricklyPotter

Posting a few pics so that there is a record of them when they sell on etsy and disappear from my shop:

Image

These are ‘magic’ salt shakers. There is a hole in the bottom that you put the salt through:

Image

The salt stays put when the shaker stays put – and when you shake it, the salt bumps into the top of the shaker and bounces back out of the same hole. It’s a neat idea that I’ve been playing with for a few years. The first generation were just round. The second generation had many small holes. But alas, salt gets wet and clumps and then doesn’t come out of the many small holes – or, worse, doesn’t want to go in. So a big hole it is. They also had the problem that there was nowhere to hold them. So I put ‘handles’ on them. But now they looked like hands – so they needed the face. The feet also came because they completed the form. Also, they allow me to glaze the bottom, and give the pot a ‘lift’ – as if it is floating on air.

People who saw them, other than saying how cute they were (more on this later), said they look like ghosts – or like robots. More specifically, ‘Daleks’ which I just found out about, not being a Dr Who fan in any way. The most interesting thing I heard was that they looked like Whirling Dervishes. I am sure Rumi wouldn’t mind.

Cute – who would have thunk it, I set out to do serious pottery and ended up with cute. I’m learning to embrace it. I still think form is important and can recycle the clay of a 6lb bowl because I didn’t like some minor detail about its foot, curve, or rim. But a sense of humour is important, as well as a sense of play. These salt shakers are a lot of work to finish, and they can’t be sold for that much money, and they are definitely not ‘serious’ – I see Hamada, Leach and Lucie Rie turning their noses. But (a) serious is a myth. And (b) fun/funny/cute/weird have a sense of play and wonder, which is a raison d’etre of their own – as valid as that of ‘serious’. They are Martial’s epigrams. Or consider that Yehuda Halevi wrote the Kuzari http://en.wikipedia.org/wiki/Kuzari, but also the following small tongue in cheek miracle of a poem:

עפרה תכבס את בגדיה במי

דמעי, ותשטחם לשמש זוהרה

לא שאלה מי העינות עם שתי

עיני, ולא שמש ליפי תארה

“Ofra washes her clothes with the waters of my tears and spreads them out to dry in the sun of her splendour.She has no need for spring water having my two eyes, nor for the sun, having her beauty”

I’m still serious about my bowls. But I’m trying to change that and let them breathe a bit too. I’ve decided to put spirals in a few as a test – they’re usually very smooth, for functional considerations. But these:Image

small dessert bowls are not smooth, and still functional – the bottom is still a nice C shaped curve and if you’re putting ice cream where the spiral is you’re probably having too much ice cream :-p You may notice that I got my tea dust glaze to work again, which I’m really happy about. It’s nice and golden and ideally forms gold flecks in a clear matrix, and only forms a continuous matte surface where it’s thick. I also developed a new bluish white, seen on the salt shaker – that goes a nice light powdery blue on top of the tea dust:Image

By the way, white is even harder to photograph than black. Two of my favourite colours – and all their nuance is lost in photos, 90% of the time.Now that the tea dust works, I need to get my turquoise to work again, since they go so well together. It has been giving me grief and pitting a lot, and not small meaningless pinholes, but craters that go all the way to the clay body, with sharp edges – pots for the shard pile. I reckoned that since it works at cone 6 as well, I may as well put in tiles to Ann’s cone 6 firing and see how they behave:

IMG_8550

The rightmost is the problem one. It did not pit. Which means the problem is either with the clay body or with the firing. I am inclined to think both, since there are well known problems with many clay bodies of a certain company that shall remain nameless. Also I have been firing very fast to get my oil spot glaze to work, following Tom Turner’s recommendation. I think this doesn’t leave the strontium carbonate in the glaze enough time to dissociate to strontium oxide and carbon dioxide, hence the pitting. The above tiles are on Laguna Frost Porcelain for ^6 which is a pristine, very well formulated clay body. And fired to a perfect cone 6 using Ron Roy and John Hesselberth’s schedule. So, Problem solved? not quite. Notice the white spots on the middle two tiles? that’s where I soaked them in lemon juice to see if they leach copper. And they do – as would the rightmost one except that I didn’t bother with it. the second from the left is much better but still has tiny white specks where the glaze was super thick – so, it’s borderline useable – It’s a very pretty glaze for surfaces that don’t come into prolonged contact with acidic foods. The one to the left is very stable, and has a surface feel that is very satisfying to the touch – not smooth, slick or satiny but not dry and rough either. The only trouble is that it’s a shade less blue and more green – still pretty but not as flashy as the other three.Going back to look at the base glazes before copper addition, I see this:Image

Where a non potter sees just four white tiles, a potter sees the top left one is a bit shinier and more yellow, and the bottom one is a bumpy surface – that’s the base for the problem glaze. So glaze composition does play a role in this. Although it is very similar in chemical composition to the one above it (btw those would be the two right  tiles in the turquoise photo) it produces a different result, in a way that is surprising to me. You learn something new every day, if you try. More importantly I am very happy with the left most tile, happy enough to start glazing a few magna opera again!

Snow!

A week of rest should be enough. I really meant to go back to the studio and make stuff. Mostly glaze testers (small bowls and cups) but also a few bowls and carafes.

But then it started snowing.

My studio is 6km from home as the bike flies.

Vancouver is not equipped to deal with snow. Why clear the streets when tomorrow’s rains will wash the snow away (not before turning it into magnificent puddles of black slush that looks like a piece of road until you step into it, ankle deep).

So I take the lazier option, and postpone throwing till tomorrow. It doesn’t help that I got a text from Ann that we need a better heater in the studio and that she will finish her 18 inch particle bowl and go home.

So for some ‘pottery porn’…

I fired the gas kiln on Friday, almost by myself (supervised by qualified firers but uninterrupted).

I did get a pretty nice (as in, I like it!) crackled celadon sake bottle:

Image

 

Image

With one iron spot, but oh, embrace the accidental, wabi sabi and all that.

I’ll put it on my Etsy store as soon as I can get two matching cups fired.

This was a sake bottle I’d meant to give to the electrician who was supposed to hook up the electric kiln and never showed up.  

Other than that I was more pleased with other people’s results than with mine. The reason is that I had mainly tall pots. That means you put them on a tall shelf that gets less reduction. It also means that I chickened out and didn’t glaze them thick enough so the celadon got washed out mostly (The sake bottle was shorter than the others so I was less afraid of glazing it thickly and I was sure that the glaze would run. It didn’t).

Danny in particular got amazing copper reds, an astounding blue celadon (my own, from the batch that’s sitting on my personal shelf, just thick enough!) and consistent carbon trapping in his Shino

And to the facebookless:

Image

 

I did get two pretty nice taller bottles. One fatter, fading to white on the neck:

Image

The other taller, darker neck and lighter body:Image

And a carafe. I like the way this one turned out, although I may refire it with some more glaze to get a deeper blue:Image

It holds a litre, is not too heavy and the indents along the sides actually do help to grip it. I think I’ll make more of those. The shape is hard to get though, it should flow and be curvaceous but not fat, and all in all should be tall and narrow but not straight sided.

The surprise in this kiln was a bowl I had glazed to be fired in oxidation. It got forgotten at the Shadbolt and never made it to my studio where it has every chance to be fired in oxidation. Instead I fired it in reduction, “because it was there”. I meant this as a test of sorts, I don’t particularly like the shape.

The results amazed me. The rim is the usual turquoise that got partly reduced for an almost peach blossom quality:

Image

Something to explore: a little less copper perhaps would create more blue/purple mottle.

The outside rim was the surprise. I had quite forgotten what I’d done with it, three months ago:

Image

And then I remembered. I had a glaze that was deep green in France. It was higher in alumina than the other one and I was sure that reduction would make it a muddy liver colour so I never tried to see what it would do. It turned out that the source of alumina matters a lot. I compared my notes this morning and the French base had alumina from clay, whereas the base I used here had alumina from the Feldspar. So while they were the same in terms of alumina and silica content, the new base was far more alkaline. This explains two mysteries:

1. Why the bowl worked in reduction,

2. Why I kept getting a deep blue and not a green every time I tried to use that glaze in oxidation.

Which, of course, opens up many new avenues for glaze testing.

I’d better get to the studio and work

As soon as the snow stops.

 

 

Another Tweet

Make It is over and I’m still reeling. It was an amazing experience. I’d been quite terrified of the scale of the event, but needn’t have been. I have come out with renewed faith in my ability to communicate my craft to people, as well as a new appreciation for my strong points and my weak points. I now know exactly what I want my booth to look like at the next craft fair, and how to do it. It wasn’t a bad booth for a first time, though.

And yes, I broke even, in fact, way more than even so I’m pretty stoked.

Thanks for everyone who made it happen and I hope to keep being a part of it in the future!

Also – starting an etsy store. I’ve just put up a few mugs and my gorgeous red pitcher for sale.

Taking pictures of my stuff is challenging, me and my black glazes. “Use natural light” they say. Hello World… I’m in Vancouver, and my place faces north. Still, we’ve been having some sub zero temperatures and clear days, so I didn’t do too badly, I think.Image

Image

Image

We’ll wait and see how it goes.

A Tweet

I’ve been silent:

Built a clay trap. Dismantled it. Put up shelves. Got my kiln. Got stood up by one electrician and found another. Made bowls. Big bowls, small bowls, medium bowls. Made salt shakers to make my table look good. Did a sale at UBC where I sold mostly big bowls. Did a sale at the guild where I sold mostly red and green mugs. Had my first bisque, my first glaze firing. Two big bowls pitted, all the small ones did too. The salt shakers crawled. Bisqued again and reglazed. My second glaze firing: my turquoise is giving me grief and three big bowl make it to the dumpster. The oil spot works. The two iron reds work. The tea dust works too well (much dust, no background). The reglazed small bowls look wild – red and yellow and teal. Get lights. Get wrapping paper. Get table covers. Pack, load, unpack, set up my booth. And now I’ve just finished the second day of the largest craft fair I’ve been in – Make It Vancouver, 250 vendors. Two more days to go – looks like I’ve broken even so far – maybe I’ll make some money on the weekend. Can’t wait for the quiet studio life, throwing and testing new glazes…Image

 

PS and here too, it’s red and green mugs all the way down!

The Trap (part 2)

This one:

Image

Ignore the blue celadons for a second. Those are interesting too and we’ll get back to them in a minute. But the middle pot, a carbon trap shino that actually trapped carbon (as seen around the rim).

For many people this is a common occurrence. But for some reason the carbon trap shino at the Guild had not been trapping carbon. Since I’ve been with the Guild I’ve had it kinda, sorta, trap some carbon on the handle of a mug, once. And the rest of the time, nada. Just an orange glaze with a tendency to crawl.

The reason given for this used to be that ours is an updraft kiln and it’s “hard to get carbon trapping in an updraft kiln”.

You may have been following the trials and tribulations of me learning to fire the kiln. Well, Suzan Marczak who’s a firer in the Guild likes to say that the kiln ‘fires itself’. In a way, it can – it has a sweet spot,  a narrow range of parameters where you get good reduction, a good temperature climb, and a good firing. And the kiln hasn’t changed, so why the problems?

A bit of pottery geekdom:

To know what the temperature is, and how much reduction you’re getting, you can use a device called an oxyprobe. This gives a number (in millivolts) for temperature, and a number for the amount of carbon monoxide in the kiln.

The other way is to ‘sense’ the kiln, by listening to it, seeing the colour/size/behaviour of the flame coming out the chimney. And for temperature, use a pyrometer, and pyrometric cones, that bend after a given amount of heat work has been reached.

Our oxyprobe had been dying for months now. And now we got a new one. So we have a new toy but we don’t quite know how it works. Which means we go back to the cones-and-flame system and just record the numbers from the probe, to learn, again, what they actually mean.

Over the last few firings it turned out we had been going into reduction a little later than we thought. Not drastically so, because we were still getting the reds and celadons to work. This time we were going to go by the cone – we would look at the spy hole early and catch cone 010 on time, before it’s flat on the shelf.  And that gave me the idea to try and see if the shino would work this time.

Firing Fridays. Gotta love those. There I was, on a foggy, rainy day, before sunrise, lighting the kiln again. But this time there is nothing to relate. Not tales of heroic fights to get the kiln to move. It simply cruised through the firing without stalling. And we did catch cone 010 on time. Suzan told me to give it another inch of gas, and the kiln just went into reduction all on its own. And my test cup is the result – finally, in our kiln, shino as it should be. As long as you reduce early enough (OK. And put the pot in a good place for carbon trapping).

The rest of the day was unproductive as only a firing day (wake up at 6AM, go to check the kiln every 30 minutes) can be. But I did share my excitement about Thierry bowls (see https://pricklypotter.wordpress.com/2013/11/04/the-trap-part-1/) with Suzan, and so Friday was big flat bowl day. I made a single pot the entire day… But it was very nice. Ann (GolemDesigns) saw the bowl stiffening up on the table outside and took a picture of it, stark white against the rough table, in the dying November light:

Image

It’s not as flat as Thierry’s but the inside curve is perfect. Now who will fire such a huge monster in the gas kiln. How will I glaze it assuming it makes it…

The other interesting thing was the blue celadon test. During a recent online pottery geek discussion someone reiterated a piece of received knowledge about blue celadons – namely, that using potassium as a flux is better for the colour than using sodium. An online friend I have questioned this, and I decided to put it a small test. Design the same glaze twice – everything being the same except one will use as much sodium as possible, and the other potassium.

I made four cups – two of each. To be put in the kiln in pairs. And here they are:

Image

Sodium left, potassium right.

and the other pair:

Image

I leave it to you to judge which one is more blue. I found the results surprising, also because it seems the right one is more matte than the left one, in both pairs.

Another celadon. That worked only partly.

The part that kinda worked:

Image

The part that kinda didn’t:

Image

A side view:

Image

Even where it’s blue, it’s not the perfect blue that the other celadons are. This was placed on the edge of a tall, cut, uncapped shelf, opposite from the spy hole (open it – get oxygen in – less than perfect reduction). My fault for making it so tall. I made it to see how tall I can go by pinching a pot, adding a coil, pinching another section, and so on. Pretty tall it turned out, about a foot. But firing this tall guy (I think it’s a vase but I may be wrong) was never going to be easy. I console myself with the fact that at the Musée Guimet in Paris there is a celadon pot just like this: half reduced, half oxidized. The magic of atmospheric firing!

Another partner in crime on the tall shelf:

Image

Just the spout:

Image

Taking pictures of black pots is hard. I wanted to show the nearly metallic, matte surface. This pot has a friend from a previous firing:

Image

We had dinner guests two days ago, and one of them thought the handle on that was metal!

I like the shape of the second one better, but prefer the glaze of the first one. It also pours much better due to the slight flattening of the spout at the very end. The quest for perfection is never done.

And to finish, from the drama of tall pots to the comforting homeliness of cereal bowls… I had the hardest time glazing these – my glazes are usually black, or dark, or dramatic in some way. Who would want to eat cereal out of a black bowl? A celadon would not work since the shape of a cereal bowl has to be simple, dictated by its humble function. But celadon excels in accentuating an elegant form.

The solution:

Image

My turquoise glaze saves the day and provides a nice contrast to the yellow fake ash. The inside is another yellowish glaze, one that’s more durable than the quite soft fake ash:

Image

Eight of them, and they all worked. It’s good when things come out the way you want!

Edit – people have asked for pics where they can see the celadons better – I’ve taken new ones, in three different exposures. By the way, you can see a place where some copper flashed onto the Na celadon, turning the rim a bit pink! Na left, K right.IMG_8265 IMG_8266 IMG_8267