Making and decorating pots

Making this pot brief overview

1. Clay prepared2. Pot thrown on potters wheel then turned3. Individual pieces dry then glued together with

slip.4. Pot burnished and a coat of slip applied then

burnished.5. Decoration planned on paper, then transferred

to pot before firing. 6. Figures blocked out then details painted on.7. Pot fired some colour added after firing.

Making a pot

• Pottery is made from clay - a sedimentary rock made up of very tiny particles of various minerals. The exact composition is dependent on which rocks were eroded to form the clay originally.

• Attic clay is unique (but then so are all clays)- and uniquely suited to a particular method of potting which the Athenian potters miraculously discovered and exploited. Attic clay contains iron – hence the red colour when fired.

Making and Decorating Athenian Red Figure vases

•The first stage in making a pot is to dig the clay out of the ground. Pieces of grit or plant matter must be removed before the clay can be used. This was done in ancient times, as it is today, by mixing the clay with water and letting the heavier impurities sink to the bottom. This process could be carried out as many times as necessary. When judged to be sufficiently fine, the clay was left to dry out to the required consistency.

• Collected clay was dried and broken to the small clod, then rubbish was removed. After that, it had to be thinned with water and washed clean of all impurities such as sand roots. This process was repeated several times and it was dried to a thick paste. This was stored in a humid room till it became sticky enough to throw on the wheel.

Making and Decorating Athenian Red Figure vases

• To make a vase the potter kneaded a lump of clay of suitable size and placed it centrally on the flat surface of the wheel.

Making a pot

• Scenes on the vases themselves show that potters' wheels were discs, presumably made of wood, clay or stone, about two feet in diameter, with socketed bases fitting over low, fixed pivots. It seems to have been usual to have a boy, presumably an apprentice potter, to turn the wheel by hand.

• As the wheel revolved, the potter drew the clay up into the required shape with his hands.

Making a pot

• Particularly large vases were thrown in sections, and in the case of shapes such as cups, the foot would be thrown separately from the body. The handles of most shapes were hand-made. When all the components had been allowed to dry for about twelve hours, they were glued together with clay slip.

Making and Decorating Athenian Red Figure vases

• So how do you get a picture? You make a pot the regular way, and let it dry a little ("leather-dry"). Then you mix a little of the wet clay with a lot of water, to make a kind of paint (called the slip), which you use to make the black part of the picture. (You can't see it now, because it is all the same color). And you let the whole thing dry.

Making and Decorating Athenian Red Figure vases

• The rough outline was drawn on the clay with charcoal: this normally disappeared when the pot was fired, but if the clay was soft an impression was sometimes left.

Making and Decorating Athenian Red Figure vases

• After an initial drawing (probably with charcoal) the artist has painted in the complete figure using the refined clay slip as paint. When fired the details will turn black.

Making and Decorating Athenian Red Figure vases

• The second stage was for the painter to go round the outside of the figure with a thin brush (approximately 5mm wide) and paint a line to enclose the figure completely. This line can very often still be detected on the finished pot. It will of course be BLACK after the pot is fired.

Making and Decorating Athenian Red Figure vases

Relief line• Next comes the detailed drawing within the figures

(represented by the thin dark red line in the picture). On the finished pot this line is remarkably consistent in width, and usually "sticks up" in relief.

• We don't know how it was done - whether with a very fine brush or a syringe special tool (like those used for icing cakes). The latest theory is that a series of tools with hairs attached could have been used - dipped in the clay paint and laid on to the pot to make curves, spirals or whatever.The relief line, drawn with "refined" clay will turn black after firing.

Making and Decorating Athenian Red Figure vases

• Now the background is filled in with black paint using a broad brush (the reason for the 5mm line now becomes clear). The "paint“/ slip is a refined version of the same clay from which the pot has been made, and so there is no great difference in colour until the pot is fired.

Firing a pot: Black and Red

• Red figure is done all with one type of clay. The clay found near Athens has a lot of iron in it, so it looks black when it is wet. But if you fire it in an oven where there is plenty of air getting in, the clay rusts, and turns red. This is because the iron mixes with the oxygen in the air. If you fire it in an oven with no air getting in, the iron can't mix with oxygen, and the pot stays black. So you can have either red or black pots.

Firing step 1 Oxidising

• In the first stage of firing, oxidising, plenty of air was allowed into the kiln, and the temperature was gradually made to rise to around 800º C. At this point, the vase turned a bright orange-red, as the oxygen in the atmosphere combined with the iron in the clay to produce (red) ferric oxide.

Firing step 2 Reducing

• When the potter judged that 800º C had been reached, he shut the air vents and introduced damp material in the form of green wood or even bowls of water.

Firing step 2 Reducing

• This produced a reducing (oxygen-poor) atmosphere in the kiln and the red ferric oxide was converted to (black) ferrous oxide, so that the entire pot turned black.

Firing step 2 Reducing

• The temperature in the kiln continued to rise to around 945º C. The intense heat caused the fine particles of the clay of the coated areas of the pot to 'sinter', that is, to fuse together to form a hard, smooth, almost glassy surface.

Firing step 3Oxidising

• The temperature was allowed to drop, and at about 900º C the ventilation holes were opened up, oxygen returned to the kiln, and the Black ferrous oxide of the unpainted areas converted back to Red ferric oxide, so that as the kiln cooled down these parts turned orange-red again. The sealed surface of the sintered areas does not let oxygen back in and so remained black.

• The pot after firing: it will now be burnished (polished up) and is ready for sale or use.