The Laboratory: Tools and Conservation Procedures
by G. Dionisio
The Conservation Lab was established in 2009 following the results of the 2008 excavation during which a rich ceramic deposit was found in two rock-cut tombs in the cemetery Area E (Tombs 228 and 230).
The need to insure that excavated materials was preserved for the future as meaningful sources of information about the past, led to the creation of an equipped laboratory where could be making all the necessary operations for the ceramic vessels conservation (cleaning, fragments reassembly, integration of the missing parts and final protection).
The Conservation Lab operates primarily on Red Polished Ware ceramics, especially jugs, juglets, bowls, jars, basins and pithoi from the tombs (Area E) and the Workshop (Area A) .
These objects are often in fragments and present the same type of surface degradation because they are characterized by thick and hard coatings of limestone and sometimes silica. This alteration results from the characteristics of the soil deposition (calcareous soil and quartz veins).
Therefore, the restoration focuses mainly on cleaning operations which are carried out mechanically with a scalpel in simple cases. To more complicated cleanings we use chemicals as chelating (Citric Acid and Bisodic EDTA) and ion-exchange resins (Amberlite IR 120H®) whose action loosens the bonds between the molecules of the inlay and allows their subsequent removal with a scalpel.
The fragments bonding is carried out using a vinyl resin called Polyvinyl acetate (K60®) while the integration of the missing parts is carried out with gypsum and/or Polyfilla Interior® pigmented.