Finished Wares

This image is of one of the larger vessels, just out of the firing, but before a final cleaning and treatment with a very fine coat of beeswax polish that protects the surface and enhances the shine slightly.

The next image below is of the other side of this pot.

The blushes of colour appear somewhat random, but there is a certain amount of control as the way they are packed within layers of materials does change the way the burning happens. They also sit in the embers which protects the carbon blackening from burning out, while the exposed areas are lighter where the carbon burns away and the flashes of colour can been seen.

Some were fired upright, some on their sides and some upside down.

The majority of Bill's vessels were this type, which is a beautiful shape that shows off any colouration on the shouder and side and also provides a pleasing basic form.

It has been the basic shape of many functional and decorative vessels through the ages, but Bill does not often get round to sticking on handles or spouts!

The flat pieces are Bill's take on replicating the form of the neolithic jadeite axes which he has a bit of fixation about!

They are made by shaping and then carving blocks of clay, followed by polishing and slip coating like the pottery vessels.

A range of colours and hues were obtained.

Many of the pots were reasonably black, but the lighter areas were often blushed with pink.

The whiter stoneware clay used provides a better paler background colour than standard stoneware, where the darker colour is less attractive in contrast to the paler whiter clay surface. That clay also burnishes well, even without the fine slip coatings. It has a very fine grog content, which helps to make it stronger.

Some of the larger pieces were damaged in the firing, a combination of things falling on them and thermal shock.

However most of the pieces survived intact.

Bonfire Firing

The more open packing, or where the foil had disintegrated allowed the carbon to burn away, created paler patches of un-affected clay. But those areas were then coloured by the flashes from the other materials.

The next day after the firing the containers of pots were excavated and unloaded.

The pots in individual tins seemed to be blacker, as the oxygen had been more starved and so the carbon blacking had not burnt away during cooling.

The bonfire was a large pile of brushwood and hedge clippings, in places more of a compost heap than a sensible source of fuel!

The packed pots were buried around the bonfire, pushed in under the fuel.

The fire was ignited in several places helped by diesel soaking. However the dampness of the fuel in places meant that it did not all burn and so a couple of hours after the firework party had finished, some of the pots had to be dug out of the unburnt parts and subjected to a new firing, using rebuilt stacks of branches.

By midnight the pots had all been subjected to sufficient heat.

The packing was not done with any scientific rigor or recording, so the resulting colours were not able to be attributed to particular elements.

It is possible that the aluminium foil contributed to the colour flashes as well, as it was usually damaged by the fire.

Sawdust was packed around the pots within their coverings. That produced the carbon blackening and was fuel to help burn the other packing materials.

Also packed around the wares were an assortment of materials that would combust and provide flashes of colours.

Thes included copper filings and wire, iron oxide powder, common salt, dried coffee grounds, tea bags, seaweed, bay leaves and other organic stuff!

These were choosen to provide colours from the traces of sodium, potassium, iodine, copper, iron and other "salts", which each burn to produce subtle flashes of various colours.

The pots were wrapped up to protect them from the fierce thermal shock of the bonfire.

Some were placed in tins with lids, some wrapped in aluminium foil.

3 metal sheets were bolted together to form a simple shelter, inside which the pots were loaded. This was meant to protect the pots from extreams of heat and things falling on them.

Making

After drying the pots were coated with terra sigillata slip and then burnished by rubbing with the spoon again, this time by hand.

Another layer of slip was applied and that was burnished by polishing with a soft cloth. Some pots were given another coat.

The slip was made by mixing powdered ball clay with water, sodium silicate and and soda ash. That suspension was left to settle out, the larger unwanted clay particles sank to the bottom and were discarded. The finer clay slip stayed at the top of the jar and was decanted with a turkey baster syringe for use.

The slip was applied using a flat sponge on a stick, starting at the top and applying rings of slip, with an overlap, so that all the surface was covered with two layers and any drips were caught during the application below.

Bill's pots were thrown using a white stoneware clay - AWS1G from Spencroft ceramics.

They were turned and then polished with the back of a spoon while rotating on the wheel.