The Effect Of Conservation Treatments On Organic Residues In Archaeological Ceramics

Abstract

Conservation treatments, while focused on preserving the physical form of a ceramic vessel, may inadvertently have a negative impact on other information stored in preserved organic residues that may remain on or in the object. This research investigates the effect of common conservation treatments on the preservation of organic residues in order to better understand how conservation treatments commonly used in the field and laboratory can affect the integrity of organic residues in archaeological ceramic sherds. Olive oil, an organic residue that is frequently found in the archaeological record of the Near East, was applied in an experimental setting to the surface of archaeological ceramic sherds. The sherds then underwent various conservation treatments, such as mechanical cleaning, soaking in water over various periods of time, and acid cleaning. Residue retention was quantified by organic extraction followed by gas chromatography-mass spectrometry (GC-MS) analysis. The results suggest that increasing the soaking time of a sherd in water decreases the amount of residue retained, and the addition of mechanical cleaning further reduces residue retention. The data gathered from this study can assist in predicting the condition of organic residues on ceramics based on previous conservation treatments and shed light on the integrity of organic residues on previously conserved objects.