The ancient pottery workshop
Text: Avgi Kalogianni | Photos: Yannos Kourayo’s archive
In a quiet and rather off the beaten track neighbourhood of Paroikia known as Tholakia, where tourists are rarely seen, there’s a house different from them all.
In the basement of the house of the Skiadas family neither wine barrels nor can tools be found. In the house basement one can see ceramic kilns and cisterns from an ancient pottery workshop built upon the ruins of an even older house!
Due to the great development of Paroikia in the past 30 years or so, a lot of rescue excavations have taken place, so now the exact positions of the city walls, the cemetery, the temples, the houses and the workshops of the ancient city have been identified. Tholakia seems to have been the… industrial zone, as, just a bit further away, a sculpture workshop has also been found in the plot owned by Irini Glypti.
The workshop was dug up from 1986 to 1988 and it was the first such dig carried out by Yannos Kourayos since he took up the position of the island’s appointed archaeologist. Actually, in 1999 the rest of the workshop facilities were revealed in the plot right next to that, and he himself went on with the dig in collaboration with archaeologist Apostolos Papadimitriou.
The workshop in the Skiadas plot is a wonderfully organised workshop for Hellenistic pottery production. It comprises 6 kilns, 2 cisterns and a number of auxiliary rooms. The central kiln is made of small schist stone slabs. It is 2.50 m. in diameter, 3 m. in height and an entrance 1m. wide, as well as two ventilation windows, through which the vessels were placed on a stone grid made of large schist stone slabs. The other 4 kilns were made of archaic jars of the 7th and 6th c. B.C., after their base and neck had been cut off and the rest of the body was built into the wall to be used as a kiln. The jars were typical examples of the Parian workshops, but similar ones can be traced everywhere in the Cyclades.
One of the cisterns is floored with schist stone slabs, has a marble drain and a number of other structures suitable for processing clay. A room with mosaic floors dating from classical times was converted into the second cistern. It seems that potters turned the abandoned house into a workshop 200-300 years later. The dig went on onto the public road right in front of the plot to reveal the entrance and two more kilns, while at a depth of 2.50 m. ruins of a strong wall from archaic times were found and under that, at a depth of 4 m., two graves came to light.
The workshop used to produce various types of vessels, such as bowls, amphorae, oil lamps as well as beehives and roof tiles, for which the larger kilns were used. This large working space was in operation between the 1st c. B. C and the 1st c. A. D., when Paros was an important pottery producer, thus meeting the needs of clients both on and out of the island.
It is an extremely important workshop as it is the first one to have been found on Paros. For the best protection of the ruins, it was decided in 1992, with the owner’s excellent collaboration and consent, that the excavation would remain intact in the basement of the modern building on top of it.
It is well known that in Greece we are really fond of antiquities as long as they are not found in our own plots of land! The solution found for this particular excavation proves that the ancient and the modern can happily coexist on Paros!
The ancient ceramic kiln
The ceramic kiln was a temporary two-storey structure, built by the ceramist himself using mud bricks, broken pots and clay. It consisted of an underground chamber comprising the fire feeding pipe and an overground domed chamber, usually round in shape, where the raw vessels would be stacked. The grid dividing the two spaces allowed flames to come up to the vessels. On the ceiling an opening, which could be shut with a slab, enabled smoke to escape and oxygen to enter. The large side opening through which vessels were entered into the kiln was completely built in after the kiln was filled and would open again after firing. The kiln had to be repaired or completely rebuilt after every firing session. Two holes on the side allowed the ceramists to control the fire by the colour of the flames and the trial vessels placed inside for that purpose. Success was a matter of both experience and luck.
Vessels would only be fired once but they followed three subsequent phases.. With the fire constantly being fed for 8 or 9 hours, temperature would reach 940-950˚ C. Vessels would glow in bright red due to the oxygen entering via the opening in the ceiling, the side holes and the feeding pipe. At that point the ceramist would feed the fire with green tree branches so that smoke would be emitted and he would then block the two openings. The temperature being about 900˚ C and with carbon monoxide from the smoke, the air inside the kiln was turned from oxidising to reducing and vessels would get completely black.
How does red result? How come two completely different colours, black and red, result from the same substance, clay?
With this question in mind I went up to Lefkes to meet potter Kostas Fifas at Lefkes Ceramics. And here is what I learnt
They don’t get black from the smoke, as the smoke from the fireplace makes the house walls black. This is coal and it would burn at the 900+ degrees inside the kiln. The black colour is produced because burning takes place under a lack of oxygen since airing holes remain closed, so it gets the necessary oxygen from wherever it is available, in this case from the vessels themselves. So for the fire to keep burning oxygen is stolen from iron trioxide (Fe2O3), which is what makes clay red, thus changing iron trioxide into iron monoxide (FeO), which is black.
Still, the ceramist is really clever and does not want the vessel to get completely black, therefore, the airing routes get reopened so that oxygen can enter, when reduction gets to the degree required for the reds to turn black, and these are the thinly layered ones, whereas the thickly layered ones remain red as they contain more oxygen on account of their greater mass.
As for the painter, he is a real master, as he uses only one colour, red, which is thinned clay, for his whole composition. Finally, he uses a thicker layer of red on parts where red needs to be maintained. What is extraordinary is the fact that the drawing remains practically invisible as all is red until fired.
The whole process required high precision in colour preparation, which had to be very fine-grained, the drawing which had to be thick enough to resist reduction, but not too thick or it would not cling onto the clay and chip during firing. All this handling had to take place under certain degrees Celsius, at times when Celsius degrees or pyrometers had not yet been invented. Essentially, only in theory do we know how all this was done and, as far as I know, nobody has achieved the same results using the means of the time.
PS. In order to visit the Ancient Pottery Workshop a permission is needed from the Ephorate of Antiquities, but you can easily get a glance through the fence, following the road indicated by the sign on the ring road of Parikia.