experiments and disasters

as always when I decide to try something new there are plenty of pots that don’t work. added to which the black clay is very risky stuff and dunts (cracks on cooling) easily.

five or six pieces from this firing are for the hammer …. but if you don’t try new things life gets very boring.

this is very sad. I think it must be that I used different glazes inside and outside it; it cracked while it was cooling.

the firing was pretty smoky for the first half of reduction, then clearer and very slow through the 1200’s, culminating with a half hour soak reducing with a  flame at the flue outlet, the pyrometer reading 1252 C, and the last cone, eleven, one third over as you can see. the kiln fires pretty unevenly, so the slower, and the more soak the better. it took from 10.30 at night to 6 pm the following day. the shino benefits from this slow firing, though this time you wouldn’t know it – I put it on porcelain surfaces, which are never very exciting with this glaze.

I had three new glazes, and the Rhodes crackle slip, which I have always meant to try and never got around to – Anne Mette Hjortshøj uses one, so I was inspired to try it at last. my opaque glazes will not show much of a slip, so I found two interesting glazes to try from the late Emanuel Cooper’s book, the Potter’s Book of Glaze Recipes – 309 delicate chun glaze, and 331 white opaque matt glaze, which is “semi-transparent, matt, opaque” in reduction, bit of a contradiction in terms but ..

first mistake was overlapping either of these glazes with my dolomite coloured glazes – here the cobalt running into the chun is not nice at all. the other new glaze was bought specially as a liner, a commercially mixed oil spot – I was feeling lazy. serve me right – that’s probably what cracked the black bottle.

this is the crackle slip on a scored small bottle in a buff clay, based on st thomas, with the chun over it. chun runs like hell and you need to have a foot which will trap it to some extent – unlike this one.

this beaker has a foot that can catch the big globules. one has run over, but it contained itself, didn’t stick to the shelf and break off. on the porcelain layer the beautiful delicate blue of the chun where air bubbles are trapped in it is shown best. the upper part and the inside have the crackle slip under the glaze, and bless me if this pot isn’t waterproof! it looks like the last piece you would expect it of. pots number fifteen and sixteen on the web page have the chun over the crackle slip and it has worked well there too.

here the crackle slip has really gone overboard and started peeling off under the fluid chun type glaze. interesting, I think the peeling off is because this was one of the pieces I made with the pink grogged stoneware with some china clay powder on it. the powder has repelled the slip and the glaze. I like the texture though, I think it works.

here a similar thing has happened with the crawling shino, but as it has flaked off this is a reject. this clay with the powder is best with the very dry barium glaze.

the other big black pot with the poured shino is fantastic, I am just holding my breath that it doesn’t crack – a friend had one piece made in this clay that cracked after he had sold it. I have to acknowledge a debt to Lisa Hammond here, I have her card of three teabowls made in black clay with beautifully poured and dribbled shino glaze. it’s not as easy as it looks ….

I have a big tub of this black matt glaze for porcelain now and can start using it more. it needs to be in a cool part of the kiln, this was on the floor at the back.

the copper red on this piece was a total accident. it has the crackle slip, glazed with Emanuel Cooper 331, which has barium 11%, dolomite 9% – it was placed close to the bright blue saltwater rectangular brush holder, and this bottle has a swollen belly, which received the copper vapour from the blue glaze where it was closest. it’s interesting that it doesn’t absorb the copper unless it’s really close; my lovely magnesium crawling glaze is hopeless if there’s copper in the kiln, it goes pale and not so pale pink all over.

it is a nice glaze with a satiny matt finish over porcelain as here over porcelain layer. for the next firing I will try this combination on bigger pots.

the rest of the pots are here

except for those awaiting destruction ….





  1. Quite interesting my friend! Even your rejects have interesting stories. Very nice! I dont’ know, I like the little cup with the blue running down inside. 🙂

  2. You are working with some lovely materials. I really like the black clay and also the matt black glaze – esp like the colour where body edges showing through. I enjoyed looking. Thank you for sharing.

  3. Hello, Jane, I always enjoy reading the accounts of your firings and seeing your wonderful pots. Sorry to hear you lost a few pieces this time, but the piece with the copper-red blush is an absolute beauty!

    Thanks for adding me as a friend on facebook too! 🙂

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