Clay and Glaze

Donyatt Clay

We have been using Donyatt clay for many years, having first dug clay out of the Shave Lane pit in the late 1960's. This pit was started around 1900 and followed a narrow seam of approximately 3 metres depth across the top of a hill above Donyatt village. After I had removed about 40 tonnes, the local council filled in the pit with refuse, so that by the time I needed more supplies in the late 1970's, I had to look elsewhere. Digging holes is an expensive business, which is why sensible potters buy their clay from commercial concerns, but I just loved working with this clay and considered the effort to be worth while. As luck would have it, the A303 trunk road was being redeveloped and  a cutting was to be made through this same hill that contained the Shave Lane pit. To put it simply, there are two purish clays in the Donyatt area, one being almost white with orange streaks, the other a grey clay. The grey clay was being reused by the road engineers to raise part of the carriageway, as it packed down well. The other clay was no use for this task and was being dumped, which suited me just fine, as this was the clay that I was after. One potter did get the grey clay and found it bloated before it reached 100 degrees centigrade!

Donyatt clay could best be described as a high iron ball clay.
It was used in the Donyatt area in the making of lead glazed earthenware. I had noticed,  as a student studying this pottery, that there were many shards of over fired pots that were stoneware in nature. The simple updraught kilns used by potters in the Donyatt area produced a high percentage of wasters; pots ruined by the firing and thrown away or used as drainage pipes. Often these wasters were the result of the atmosphere in the kiln being too smoky or in combination with the temperature going too high. One or both of these conditions resulted in the glaze boiling away. In the case of the pots being too high fired, the clay began to vitrify and in doing so got much stronger, but the lack of glaze made them unsaleable. The potters at Donyatt were small farmers, supplementing their meagre incomes by making pots in the agriculturally quiet times of the year. Although they may have come across stoneware imported into England from the continent, earthenware was the English tradition and they missed an accident trying to tell them something. I, on the other hand, was already working in stoneware and so could see the potential of this beautiful material.

The glazes we use are a mixture of old hand-me-down and newly developed recipes. As much as possible, we use local and self-won materials in the form of clays, plant ash and rocks, to make glazes that have subtle and unique qualities and work with our kind of gentle wood-fired stoneware.
We are constantly testing materials, glazes and glaze effects in the search for new glazes and a wider colour range with in the constraints we have set ourselves. One of our constraints is the ability for those glazes to be used for single firing (also known as raw glazing or once-firing) as opposed to twice firing as so many potters do.

With the establishment of the pottery in Queen Camel, came the decision to fire all pots with the use of wood as a fuel. The aim was to be as environmentally positive as possible and add to the qualities of our work. Wood burning is carbon neutral of itself and, being locally sourced,  is low in fuel miles. However potters often burn wood in a very inefficient manner, so it was important to adopt a design that would continue the kiln efficiency developments I had been advancing with oil kilns at the old pottery near Chard.
The Fred Olsen 'Fast Fire' wood kilns served us well for 30 years but has now been replaced with my own more efficient design, 'Dora'  a lo-mass 2 chambered, double fire-box, stoneware kiln.

Dora from the firebox end

Dora from the firebox end

Raw Donyatt clay

Donyatt clay in its raw form

Wood delivery

Pine wood offcuts arrivefor next years firings

The old big Fred Olsen wood-burning kiln

This large Olsen fast firing kiln served us well for 30 years