snow and a firing

the garden and the pottery workshop under february snow after the firing; an opportunity to photograph birds from the kitchen window

a dunnock fossicking about under the peanut feeder for crumbs

a great tit

and a marsh tit; there is a pair of these nearby and they love peanuts.

the coal tit is very similar but close-up you can see he has a wide black beard rather than the marsh tit’s little goatee.

and his black cap splits in half at the back of his head.

I left the kiln two days to cool after last August’s disaster when I opened too early and one big piece cracked. everything looks fine. cone 10 went right over; cone 11 just starting to go … perfect.

you can see the soot from the reduction; some people think I am over-reducing to get this smoke and black on the bricks, but it is during the early stages of reduction, between 1050 and 1150 C. then I cut down the strength of the reduction and I get these great oranges, greens and blues from my dolomite/tin oxide glaze.

the top centre piece has porcelain on the lower half, producing the grey blue, and the base clay is the “school” stoneware, a light buff – the blue glaze is almost black on this. next to it is my mixed basically st thomas body, with porcelain over it, and the copper version of the dolomite/tin glaze, with greens and oranges.

looking in, the top shelf at the back has worked really well.

close-ups of those smaller pieces.

no breakages – I put the black clay on sand now, a tip from Sarah Purvey, so that it can’t stick to the shelf and crack as it cools.

this porcelain piece on the left has the black version of the dolomite/tin glaze; interestingly the other two pieces I glazed with this have come out a dull matt freckled green .. maybe more – or less – reduction ….. will have to think about that.

the two black clay pieces. actually I mixed it half and half with a buff stoneware; glazed with the barium carbonate glaze it stays almost the same colour as it is after the bisque firing … you can see that the unglazed bit at the bottom of the left hand one is black though. a thinner coat of glaze will give a blacker result – next time … I have a few more of these waiting to be glazed.

the bottom of the back of the kiln looks great too – top and bottom has some good examples of the blue version of the dolomite/tin glaze.

the porcelain glaze which I expected to be black has gone matt khaki – that’s fine though,

close-up of those blues – quite intense.

and one pot photographed to look its best – then the camera’s batteries went in the cold. it’s only just above freezing.

postscript – the rest of the pots can be seen here

4 Comments

  1. it has various oxides in it which combine to give a black effect – copper, cobalt, iron, manganese – and if the glaze is a bit thin, or the oxides burn off to some extent, the copper and iron can be left looking less intense, giving this dull khaki. I’m wary of making it too thick; I don’t want to cover up the impressed patterns – also it runs like mad if it gets too hot!

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