Marisia - Maros Megyei Múzeum Évkönyve 32/2. (2012)
Articles
A Standpoint on the Restoration of Medieval Ceramics 217 8. To the documentation of the restored object, information regarding the adhesive used and the work methodology are to be annexed. Modifications of the temperature and relative humidity of the air in the rooms where the pottery objects are exhibited or deposited bring negative alterations to these objects, affecting their surfaces. The restored pieces need special conditions of preservation, according to the characteristics of the synthetic adhesives and other substances used in the reconstitution process (PI. 2/2-3). However, the major threat is actually the deficient manipulation. Light coloured and easily pulverisable objects need to be kept from impurities, as their cleaning is extremely difficult. Bacterial and mouldiness contamination can be avoided through careful packing and maintaining the relative humidity under 65%, at constant temperature. Owed to the lead contents of the enamelled objects, they are known as glazed objects. Glazing is obtained at a certain temperature, when the lead oxide comes into contact with substances containing quartz. The common example for the mineral substances that embody quartz is the clay. For this reason, the fired or raw clay objects can be glazed with lead oxide, producing enamelled covering. The aspect resulted this way is a shiny, glassy surface. Infrequently, it could have asperities, which are the effect of some 1.2 mm features or of needle pricks. The lead oxide contents of the glaze can be as high as 90%, which, as already known, through thermal reaction with the quartz, forms the enamel. Restoring these artefacts, like for instance the stove tiles, requires the use of fine brushes to be cleaned without affecting the enamel and the patina, which reflect the air of the epoch. If there are decorative figures - as in the case of two knight stove tiles from the 16th century that required our intervention, the decorative motives and part of the horse needed re-modelling (Pi. 1/1-2) -, correct and minute reconstitution can only be achieved after previous documentation regarding analogies and drawings from those specific times. LIST OF PLATES Plate 1. 1-3. Stoves tiles discovered in the fortress from Tärgu Mures, before and after restoration. Plate 2. 1. Phases of a vessel restoration; 2-3. Final destination: objects display in exhibitions.
