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ta. Ispitivanja zubarskim alatkama na ivicama prelomasu to dokazala, a pokazalo se da je i glazura čvrsto vezanaza telo. Kompaktne naslage zemlje na dnu recipijentasu se lako skidale, odvajajuci se ljuspasto od površine,bez opasnosti da bi mogle povući i površinski slojkeramike, tj. glazuru.PREDLOŽENI TRETMAN: Odlučeno je da se uradipotpuna restauracija predmeta. Tok tretmana bi bio sledeci:uklanjanje stare restauracije, tj skidanje restauriranihdelova od gipsa i čišćenje fragmenata, a zatim bisledila konsolidacija i ponovno lepljenje, restauracijagipsom, retuš i završna konsolidacija predmeta.Konzervatorski tretmanČIŠĆENJE PREDMETA. Najjednostavniji i istovremeno,za predmet, najbezbedniji način uklanjanja restauriranihdelova od gipsa je mehanički. Veće površinegipsa su dobro ovlažene vodom i tako omekšan, gips jepažljivo sečen skalpelom što bliže ivici keramike. Ivicefragmenata su zatim očišćene vodom, zubarskim alatkamai iglom od ostataka gipsa.Fragmenti su bili zalepljeni, ali pošto predhodno saivica nisu bile uklonjene naslage zemlje, posuda je moralabiti razlepljena, a fragmenti u potpunosti očišćeni.Uklanjanje starog lepka počinje njegovom identifikacijomna osnovu fizičkih i hemijskih karakteristika - boje,čvrstine i rastvorljivosti. Na identifikaciji se zasnivaizbor odgovarajućeg rastvarača za ukljanjanje lepka.Test na jednom fragmentu je potvrdio pretpostavku daje predmet bio zalepljen OHO lepkom, 8 koji se kod nasnajčešće koristi. Da bi u potpunosti bila razlepljena,zdela je stavljena u plastičnu posudu sa hermetičkimpoklopcem i okružena tamponima vate koji su natopljeniacetonom i postavljeni tako da ne dodiruju keramiku.Posle 90 minuta, uz povremeno dodavanje acetona natampone vate, pod uticajem acetonske pare OHO lepakje omekšao i fragmenti su se razdvojili. Prilikom razlepljivanjaprimenjen je samo blagi pritisak na spojeve, jerako lepak nije dovoljno omekšao, jači pritisak bi mogaouzrokovati odvajanje tankog sloja keramike zajedno salepkom. Pošto aceton spada u izuzetno lako i brzo isparljiverastvarače, predmet je morao biti smešten u atmosferuhermetički zatvorenog kontejnera, a kutija je tokomtog procesa stajala u posebnoj prostoriji u kojoj jeprozor bio otvoren. 9 Usledilo je čišćenje ivica fragmenataod preostalog lepka pomoću štapića sa namotajimavate, koji su natopljeni acetonom.Čišćenje keramike od zemlje i ostalih površinskih nečistoćavršeno je prvo mehanički. Korišćene su zubarskealatke, četkice i skalpel, a zemlja se lako skidala sa čvrste,glazirane površine. Na kraju je keramika očišćena destilovanomvodom, pomoću štapića sa namotajima vate.Vata je menjana sve dok na njoj nisu prestali da ostajutragovi skinutih naslaga nečistoće. Voda je često najefikasnijirastvarač, koji se koristi za uklanjanje zemlje inemasnih naslaga sa površine keramike. Kada su fragmentibili potpuno suvi, dezinfikovani su alkoholom.KONSOLIDACIJA. I pored neophodne reverzibilnosti,veoma je teško kasnije u potpunosti odstraniti konsolidantiz tela keramike. Međutim, iako su fragmenti zdelebili u dobrom stanju, a glazura dobro vezana za telo,odlučeno je da se keramika konsoliduje, zbog nekontrolisanihuslova u depou. Istovremeno, konsolidacijom sestruktura dodatno mehanicki učvršćuje, bez hemijskereakcije sa keramikom. Obim i brzina prodiranja konsolidantau keramiku zavisi od veličine molekula smole, od8 OHO lepak je mešavina polivinil acetata i celuloznog nitrata.9 U nedostatku prostora sa adekvatnom ventilacijom iekstraktora za gasove, posebna prostorija za lako isparljive, štetne izapaljive materije je jedino rešenje.134ld not be assembled while the second handle was not remade.The significance of the object itself and the factthat only few such vessels were discovered together withthe obvious mistakes during the previous restorationwere good reasons for the curator to decide that newconservation and restoration were needed.ESTIMATION OF THE STATE OF THE OBJECT:The dish was thrown on a wheel and the clay was wellrefined.The investigations of the edge of a fragmentproved that the ceramics was relatively porous, which iscommon for the firing temperature of this kind of ceramics.7 Since decoration of the dual technique of sgraffitoand painting implies that the dish was fired twice, itwas assumed that the ceramics was quite solid. Examinationwith dental tools on the edges of fracture provedour assumption, as well as the fact that the glaze wasfirmly attached to the body. Compact layers of dirt atthe bottom of the recipient were easily taken off as theyflaked, without risk of taking off the surface layer of ceramicswith them , i.e. glaze.SUGGESTED TREATMENT: It was decided thatthe full restoration of the object was to be done. The followingtreatment procedure was applied: removal of oldrestoration, i.e. taking off the restored pieces of plasterand cleaning of fragments, and afterwards consolidationand reassembling, restoration with plaster, retouchingand the final consolidation of the object.Conservation treatmentCLEANING OF THE OBJECT: The simplest and inthe same time the safest way of removing the restoredplaster pieces is mechanical cleaning. Larger plasterareas were well moistened with water, and such softenedplaster was carefully cut with scalpel reaching asclose as possible the edges of the ceramics. The remainingplaster on the fragment edges was then cleaned bywater, dental tools and the needle.Fragments were assembled, but the edges were notcleaned from dirt before assembling, the dish had to bedisassembled and fragments completely cleaned. Removalof old adhesive began with identification based on itsphysical and chemical characteristics - colour, firmnessand solubility. This identification determined the choiceof appropriate solvent for adhesive removal. Test on onefragment confirmed the assumption that the object wasassembled with the OHO adhesive 8 , very commonly usedhere. In order to completely disassemble the dish, it wasput in a plastic vessel with the air-tight lid and surroundedwith cotton wool pads moistened with acetone andplaced so as to avoid any contact between the pads andthe ceramics. After 90 min. with occasional adding ofacetone to the pads, due to acetone vapours, OHO adhesivehad softened and fragments separated. During thedisassembling only the slight pressure was applied tojunctions. Otherwise if the adhesive had not softenedenough stronger pressure would have caused detachmentof the thin layer of ceramics together with the adhesive.Since acetone evaporates easily and quickly, the objecthad to be placed in a special room with open windows. 9Then the fragments’ edges were cleaned from remainingadhesive, using sticks with cotton wool pads moistenedwith acetone. Ceramics was first mechanically cleaned7 Medieval glazed pottery was mostly fired at temperaturesfrom 800ș do 1000ș C, its porosity depends on the quality of clay andis always over 5%. Porosity of stone, faience and porcelain, whichare made of extremely refined clay of high quality and fired at temperaturesabove 1050șC, is always less than 5%.8 OHO adhesive is a mixture of Polyvinyl acetate and cellulosenitrate.9 In the lack of space with adequate ventilation and gas extractor,separate room for easily evaporative harmful and flammablesubstances is the only solution.