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korišćenog rastvarača i od procenta smole u rastvaraču.Takođe, zavisi od fizičkog i hemijskog stanja predmeta imetoda primene konsolidanta. Izabrani konsolidant nesme da promeneni izgled predmeta, što je posebno važnoza predmete koji nisu glazirani ili imaju transparentnuglazuru. Mnogi materijali, kada ispune telo keramike,menjaju ton boje, čineci površinu tamnijom ili sjajnom.Fragmenti su konsolidovani u 5% rastvoru paraloidaB72 10 u ksilolu. Konsolidacija je izvršena metodom potapanja,jer se na taj način omogućuje prodiranje rastvorau predmet u najvećoj meri. Fragmenti su stavljeni na metalnumrežicu, koja nam dozvoljava da ceo proces obavimobez direktnog dodira sa konsolidantom, a zatim supolako potopljeni i ostavljeni u hermetički zatvorenojkanti, 60 minuta. Lagano potapanje je veoma važno, jerna taj način omogućavamo da se vazduhu postepeno povlačidok keramika kapilarno apsorbuje konsolidant. Svremena na vreme je proveravan nivo zasićenja keramikei sve dok konsolidant nije u potpunosti prodro ustrukturu, na površinu rastvora su izlazili mehurići vazduha,koje je konsolidant potiskivao. Fragmenti su ostavljenidvadeset četiri časa da se osuše, jer je toliko potrebnorastvaraču (ksilolu) da u potpunosti ispari iz keramike.Neophodno je da keramika bude potpuno suva presvake dalje faze tretmana, posto bi kontakt rastvarača savodom izazvao pojavu belih tragova i mrlja.LEPLJENJE. Pri izboru lepka je veoma važno izabratilepak odgovarajuće viskoznosti, koja je u skladu sastepenom poroznosti keramike. Porozna keramika nesme da se lepi lepkom male viskoznosti, jer će biti apsorbovanu telo keramike, ne ostavljajući dovoljno lepkana površini ivica fragmenata, što onemogućava dobarspoj. Osim toga, apsorpcija lepka ostavlja nepopravljiveposledice za predmet: na delovima oko preloma i spojevamogu se pojaviti tamne mrlje koje označavaju dokleje lepak apsorbovan; konsolidant deluje na lepak i kasnijepri rukovanju predmetom svaki pritisak na spojmože izazvati da se konsolidovani deo odvoji, štopredstavlja novo oštećenje. Zato lepak za poroznu keramikumora da ima prirodnu viskoznost.Pre lepljenja, ivice fragmenata su još jednom očišćenealkoholom i prekontrolisano je da li su ostala vlaknavate, jer samo apsolutno čista i suva površina omogućavadobro lepljenje. Fragmenti su zalepljeni OHO lepkom,11 a spoj je zatim učvršćen papirnim selotejpom.Manja količina lepka, koja je pod pritiskom iscurela naspojevima, očišćena je acetonom dok je lepak još biomek. Pronađeno je mesto jednog fragmenta koji u predhodnojrestauraciji nije bio zalepljen. Provereno je jošjednom da li se drugi fregment negde uklapa, ali poštone postoji mesto direktnog spoja, njegovo mesto je određenona osnovu dekoracije i forme i biće kasnije uklopljenu toku rekonstrukcije.Sledećeg dana, kada je OHO lepak bio potpuno suv,skinut je selotejp. Selotejp ne sme ostati dugo zalepljenna površini keramike, pre svega keramike sa osetljivompovršinom, jer će pri skidanju povući sa sobom čitav površinskisloj keramike ili sve nestabilne i slabo vezanedelove. U našem slučaju se moglo desiti da se, naizgledčvrsto vezana glazura, na nekim mestima odvoji. Površinakeramike pažljivo je očišćena acetonom od tragovaselotejpa, jer ako oni ostanu na keramici, skupljaće pra-10 Paraloid B72 je kopolimer metil akrilata i etil metakrilata.Koristi se kao lepak i konsolidant za trošnu i čvrstu keramikuReverzibilnost: rastvorljiv je u acetonu, ksilolu, toluenu, diacetonalkoholu, metilen hloridu, etilen dihloridu, trihloretilenu, etilacetatu, dimetil formamidu. S.Buys, V.Oakley, Conservation andRestoration of Ceramics, Oxford 1999., 191.11 OHO lepak je kod u najčešćoj upotrebi. Polivinil acetat spadau grupu polimera najotpornijih na uticaj svetlosti. ReverzibilnostOHO lepka: rastvorljiv je u acetonu, toluenu, etil acetatu. Omekšavau tpoloj vodi.from dirt and other surface filth. Dental tools, brushesand a scalpel were used and dirt was easily cleaned fromsolid glazed surface. At the end the ceramics was cleanedwith the distilled water using sticks with cotton wool.Cotton wool was being replaced until no marks of thedirt were left on it. Water is often the most efficient solventthat is used for dirt and removal of non-greasy layersfrom the surface of the ceramics.The dried fragmentswere disinfected with alcohol.CONSOLIDATION. In spite of needed level of reversibility,it is very difficult to completely remove the consolidantfrom the ceramics body. However, although thedish fragments were in good condition and glaze firmlyattached to the body, the decision was made to consolidatethe ceramics as conditions in the depot could notbe controlled. At the same time the structure was stabilizedby consolidation without provoking a chemical reactionwith ceramics. Degree and the speed of consolidantpenetration into ceramics depend on molecule sizeof the resin, the solvent used and finally the resin percentagein solvent. They also depend on physical andchemical conditions of the object and on the method ofconsolidant application.The chosen consolidant must not alter appearance ofthe object, which is especially important for objects thatare not glazed or that have transparent glaze. Many materials,after filling the ceramics body alter the shade ofthe colour, making the surface darker or lighter.The fragments were consolidated in 5% solution ofParaloid B72 10 in xylol. Consolidation was done by immersing,this method provides penetration of the solventinto the object to the highest degree. Fragments wereplaced on a metal grid which made completion of theprocess possible without direct contact with consolidant,and then they were carefully immersed and left ina hermetically closed can for 60 min. Careful immersingis very important, because the air gradually withdrawswhile ceramics absorbs the consolidant through capillars.The level of ceramics saturation was occasionallychecked and before the consolidant completely penetratedthe structure, air bubbles pushed by the consolidantstarted appearing on the surface of the solvent. Fragmentswere left to dry for 24 hours, since it is the timeneeded for the solvent xylol to evaporate completely outof the ceramics. It is necessary that the ceramics is completelydry before any further treatment since otherwisecontact of the solvent with the water would cause appearanceof white traces and stains.ASSEMBLING. For the assembling phase it is veryimportant to choose adhesive with viscosity that correspondsto the degree of ceramics porosity. Porous ceramicsmust not be assembled with adhesive of low viscosity sinceit will be absorbed into ceramics body, without leavingenough adhesive on the fragment surfaces, thus preventingsolid joints. Besides, absorption of adhesive leaves irreparableconsequences on the object: dark stains can appeararound fractures and junctions indicating to whichdegree adhesive is absorbed; consolidant affects adhesiveand during further handling the object, even a slightpressure can cause the separation of consolidated partwhich further causes damage. Therefore adhesive for porousceramics needs to have natural viscosity.Before assembling the fragment edges were onceagain cleaned with alcohol and checked for the remainingcotton wool fibres as only absolutely clean and dry10 Paraloid B72 is a copolymer methyl acryl ate and ethyl metacrylat.It is used as the adhesive or consolidant for fragile and firmceramics. Reversibility: it is soluble in acetone, xylol, toluene, diacetonealcohol, methylene chloride, ethylene dichloride, trihloretilen,ethyl acetate, dimethylformamid. S.Buys, V. Oakley, Conservationand Restoration of Ceramics, Oxford 1999., 191.135