A complex analytical method for parchment characterization

Abstract

Parchments are interesting archeological objects. A wide variety of modern analytical techniques have been applied in order to get better insight on parchment preservation stage as well as to contribute to their conservation and restoration. However, no practical method to help the museum workers and laboratory experts in these routine jobs exists. Several requirements have to be satisfied to obtain an appropriate procedure capable of parchment characterization as an entire analytical object. Due to the unique character of common archeological objects, non-destructive techniques or those requiring no (or only minimal) sampling, are preferred. The second problem in this method development deals with the nature of objects under the study. Archeological objects (and parchment particularly) regularly have complex shapes and structures and their origin is rarely known, and they can be found in various states of conservation. Their degree of deterioration can modify the che mical and the physical composition mainly of the surface layers, which are directly accessible to analysis. However, the information obtainable from deeper layers can sometimes be more helpful. Therefore, an application of a single analytical technique to describe parchment conditions often is not advantageous and a special experimental approach, which combines several examination techniques and chemical analysis should be favored. In this context, an assortment of five analytical techniques (synchronous fluorescence, laser induced breakdown spectroscopy, visual color imaging, characterization using high voltage application and near infrared analysis) as well as every technique alone represents one of the best choices, since it combines simplicity, good analytical performance and robustness, non- destructiveness and non-invasiveness. The aim of this work was to develop a guide procedure for characterizing archeological objects using complex nondestructive analytical methodology. Using this guide, the entire parchment analysis can be performed very fast in situ and archeological items can be identified in real time during an on-line data collection. Furthermore, it allows several constituents of interest to be measured simultaneously leading to accurate and objective identification of authentic items.