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12 Lateks je guma koja se dobija iz drveta Hevea brasiliensis,asam proizvod sadrži do 60% gume kojoj je dodat amonijak, da bibila postojanija. Guma je vulkanizovana i u toj formi nije rastvorljivau rastvaračima. Dvostruke veze polimera omogućavaju bržuoksidaciju na sobnoj temperaturi i kada se osuši dobija oblikelastične i jake prevlake C.V.Horie, Materials for Conservations,Butterwoths, UK, 199013 Barlep je akrilna disperzija, koja se može naći pod različitimproizvodnim nazivima.136šinu i prljavštinu koja se lepi za njih, a ubrzo će promenitii boju i postati vrlo uočljivi.REKONSTRUKCIJA. Pre početka rada na rekonstrukciji,keramika je dodatno zaštićena lateksom. 12 Lateksomogućava da se površina keramike zaštiti od mehaničkihoštećenja tokom rada i da se materijali i bojekoje koristimo tokom procesa restauracije ne apsorbuju,jer svako naknadno čišćenje produžava rad konzervatorai dodatno oštećuje keramiku.Na osnovu forme sačuvanih i zalepljenih fragmenatanapravljen je kalup od gline za delove zida recipijenta ioboda koji nedostaju. Uzet je otisak sačuvane drške u glinii tako je dobijen kalup u koji je onda uliven gips. Obrađenadrška je zatim postavljena na sačuvan koren originalnedrške. Po uzoru na dekoraciju sačuvane drške, oštromalatkom je urezan spiralni ornament. Na spoljašnjojstrani posude su šestarom iscrtani koncentrični krugovi,a zatim su urezani oštrom alatkom. Na kraju je gips ispoliranšmirglama visoke granulacije, da bi se dobila površinakoja odgovara teksturi glazirane keramike.Za rekonstrukciju je korišćen alabaster gips, koji jemešan sa rastvorom 0,75% barlepa 13 u vodi. Gips jenajčešće korišćeni materijal za rekonstrukciju, jer sunjegova gustina, čvrstina i toplotno širenje uglavnomkompatibilni sa slabije pečenom i arheološkom keramikom.Njegova svojstva se mogu poboljšati dodavanjemakrilne disperzije ili polivinil acetatne emulzije, čime sepovećava i čvrstina gipsa i snaga lepljenja. Relativnogruba tekstura ivica preloma porozne keramike odgovarasvojstvima gipsa, koji se za njih dobro vezuje.Postoje najmanje dva različita pristupa restauracijidelova koji nedostaju na predmetima. Za oba pristupapostoje argumenti koji ih podržavaju i opovrgavaju. Kodnas se restaurirani delovi izrađeni od gipsa izvode takoda budu u istom nivou kao i originalna površina keramike.Prelaz između gipsa i keramike treba da bude neprimetan,kada se nivo proverava prstima. Smatra se dase razlika između originala i restauracije može dovoljnonaglasiti izvođenjem retuša koji je za nijansu svetliji odkeramike. Takođe, u našoj konzervatorskoj praksi nijeobičaj da se dodaju pigmenti u gips da bi restauriranideo dobio boju i ton sličan keramici. Znači, restauriranideo izveden od gipsa ostaje beo, a zatim ga retuš činiuočljivim i drugačijim od originalne površine keramike.Kada se radi retuš na belom gipsu, mora se imati u vidustarenje retuša i njegovo ljušćenje, a time i neophodnostobnavljanja retuša posle izvesnog broja godina.Drugi pristup, koji nije uobičajen kod nas, sastoji seod izvođenja restauriranih delova koji su uvek vrlo masurfaceenables good assembling. Fragments were assembledusing OHO adhesive 11 , and junction was fixedby paper duct tape. The amount of adhesive that underpressure appeared on conjunctions was cleaned by acetonewhile adhesive was still soft. A fragment, which inprevious restoration was not assembled, was now fittedto its position during assembling. It was checked againwhether the other fragment fitted somewhere, but sincethere was no direct junction, its place was determinedbased on decoration and form and it would be fitted duringthe reconstruction.On the next day, when the OHO adhesive was completelydry, the duct tape was removed. The duct tapemust not be left for a long time on the ceramics surface,especially with sensitive surface, as during removal surfaceof ceramics and all unstable and loosely attachedparts can be lifted by it. In our case seemingly firmly attachedglaze could detach. Ceramics surface was carefullycleaned with acetone from the duct tape traces. Otherwisethey would collect dust and dirt and would soonchange the colour and become visible.RECONSTRUCTION. Before the reconstruction, ceramicswas additionally protected by rubber latex. 12Latex enables further protection of the ceramics frommechanical damages during work and avoiding absorptionof materials and colours used during restoration,since further cleaning prolongs the work of conservatorand additionally damages ceramics.Based on the form of preserved and assembled fragmentsmould of clay for missing parts of recipient walland rim was made. Print of the preserved handle was madein the clay and plaster was infused into the obtainedmould. Processed handle was then placed on the preservedroot of the original handle. According to decoration of thepreserved handle a spiral ornament was incised with asharp tool. Concentric circles were drawn on the outer sideof the dish with callipers, and then they were incisedwith a sharp tool. At the end plaster was polished withemery of high granulation, in order to obtain the surfacethat corresponds to the texture of glazed ceramics.Alabaster plaster, mixed with 0,75% Barlep solventin water was used for the reconstruction. 13 Materialmost often used for reconstruction is plaster, as its density,firmness and heat expansion are compatible withlow fired and archaeological pottery. Its qualities can beimproved by adding acrylic dispersion or polyvinyl acetateemulsion, wherewith firmness of plaster andstrengths of assembling are enhanced. Relatively roughtexture of junction edges of porous ceramics correspondsto plaster qualities.There are at least two different approaches to restorationof missing parts on the objects. For both there arearguments that sustain or disprove it. Restored partsmade of plaster should be in the same level as the originalsurface of pottery. Transition from plaster to potteryshould be imperceptible when touched. It is believedthat difference between the original and restoration issufficiently emphasized by retouch that is for one nuancelighter than pottery. Likewise, in our conservationalpractice it is not customary to add pigments into plaster11 OHO adhesive is most commonly used in our country. Polyvinylacetate belongs to the polymer group that is most resistive tolight. OHO adhesive reversibility: it is soluble in acetone, toluene,ethyl acetate. It softens in hot water.12 Rubber latex is derived from the rubber tree Hevea brasiliensisand commercial product contains to 60% rubber, with ammoniaadded to give enhanced stability. Rubber is vulcanized and insolublein solvents. The double bonds in the polymer enable rapid oxidationat room temperature. Dried latex is in form of elastic andstrong film. C.V.Horie, Materials for Conservations, Butterwoths,UK, 1990., 90.13 Barlep is acrylic dispersion that can be found under differentproduct names.