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touch and slow drying process, possibly because of thehigh concentration of montmorillonite (samples of theSlanci series taken at the St. Stephen Monastery andfrom the drill of 17-18 m depth). Some combinations ofthese raw materials led to the mass of satisfactory plasticity,that could be used for production of vessels. Afterthe results of comparative analyses are obtained, newseries of testing pieces will be made, as well as replicasof certain Vinča vessels, from more adequate raw materials.Vađenje test - pločica iz jameFiring the test-piecesD - Pečenje test - pločica na terenuPosle pomenutih opsežnih priprema, ekipa u sastavu:V. Svoboda, J. Vuković, Đ. Bogdanović, J. Vacić, T.Nedeljković, I. Stojković, D. Milovanović, D. Maksimovići B. Belošević, pristupila je realizaciji eksperimentalnogdela prve faze projekta, koji podrazumeva pečenje testpločicana arheološkom lokalitetu Vinča. Radi lakšegkontrolisanja temperature i redukcionih uslova pečenja,iskopana je jama koničnog oblika, gornjeg prečnika 115cm, donjeg prečnika 80 cm i dubine 90 cm. Takođe je iskopanai manja jama, u kojoj se pripemao žar. Da bi sekontrolisala temperatura pečenja, iz veće jame je prokopankanal za sondu pirometra. Odlučeno je da se kaogorivo koriste kiselo drvo, bor, smreka i jela. Radi zagrevanjajame za pečenje, na dno jame su položene sitnegrane, koje su zatim zapaljene. Istovremeno, u manjojjami su zapaljeni veći komadi drveta, a test-pločice supostavljene oko nje, zbog dodatnog sušenja i zagrevanja.Glavna jama je zagrevana 1 h i 15 minuta. Dno jame je,zatim, popločano odbačenim fragmentima autentičnevinčanske keramike, da probne pločice ne bi došle u direktankontakt sa žarom, što bi izazvalo pucanje. Izmeđufragmenata keramike i zidova jame ostavljena je zonaprosečne širine 10 cm, za postavljanje žara i granja.Na popločanu površinu su zatim postavljene test-pločice.Potom je oko njih prebačen žar iz manje jame, a prekonjih je postavljeno sitno granje. Probne pločice supostepeno žarene do temperature od 575 o C, na kojoj segubi tehnička i hemijska voda. Kada je dostignuta pomenutatemperatura, u jamu su dodate krupnije grane ipreostali žar iz manje jame. Ovako su, u vatri, pločicepečene oko 1 h, na prosečnoj temperaturi od 700 o C. Nakonšto je temperatura dostigla 800 o C, vatra više nijeodržavana. Kada je drvo potpuno izgorelo i plamen nestao,u jamu je ubačeno polusuvo lišće. Da bi se postiglaredukciona atmosfera, jama je odmah zatrpanazemljom. Ostavljena je da se hladi 24 sata. Ceo procesD – Firing of testing pieces on the siteAfter the already mentioned preparing processes,the team consisting of V. Svoboda, J.Vuković, Đ. Bogdanović,J,Vacić, T. Nedeljković, I. Stojković, D. Milovanović,D. Maksimović and B. Belošević, started the experimentalpart of the Phase I – firing of testing pieces onthe archaeological site of Vinča. In order to control temperatureand reduction conditions more easily, a pit ofconical form was dug, its upper diameter 115 cm, lowerdiameter 80 cm and 90 cm deep. Also a smaller pit wasdug, to prepare ember. A canal for a pyrometer was dugfrom the larger pit, to simplify temperature control. Itwas decided to use ailanthus, pine, juniper, fir. In orderto warm up the firing pit, small branches were fired onits bottom. At the same time, larger pieces of wood werefired in the smaller pit, with testing pieces set aroundit, to obtain additional drying and warming up. Thisprocess lasted 1 hour and 15 minutes. The bottom of thepit was then covered with rejected fragments of authenticVinča ceramics, to avoid direct contact between testingpieces and ember, and breaking of the pieces. Betweenfragments of ceramics and the pit walls, there wasan area about 10 cm wide, intended for ember and branches.Testing pieces were put on previously prepared ceramicsurface. The ember was transferred from thesmaller pit and put around pieces, while the brancheswere laid on them. Testing pieces were gradually firedup to the temperature of 575°C, where technical andchemical water was lost. The mentioned temperature reached,larger branches were added in, as well as the restof ember from the smaller pit. In this way, the pieces werefired for around 1 hour, at the approximate temperatureof 700° C. When the temperature reached 800° C,the fire was no longer kept burning. Wood was completelyburnt and dry leaves were added in the pit. It wasimmediately filled with ground to ensure reduction atmosphereand left to cool down for 24 hours. The wholeprocess of heating up and firing lasted for 2 hours and45 minutes.Next day, the pit was uncovered, and testing pieceswere taken out. The firing turned out to be successful –reduction was reached and no piece was broken.Pečene test - pločiceFinished test-piecesTest - pločice pre i posle redukcionog pecenjaTest-pieces before and after reductive firing129