Methodology in general
The programme consists of two stages: fieldwork on the monuments to gather the relevant information and the photographic and/or imprint of vessels, as well as processing the data collected and registering them in the specific fields of the database. As a key objective of the programme was the exhaustive identification of monuments of each region that are distinguished for this particular form of decoration, the first stage was to identify –through the indexing of literature relevant to each area– the related references to churches where immured vessels have been preserved or simply their receptacles. The first catalogue that was drawn up this way was supplemented –in most cases with many more monuments– by the research of fellow archaeologists of the relevant Ephorates in the photographic records of the latter. In many cases the restoration works of the Ephorates of Antiquites contributed to the increase of the number of churches, as the removal of the lime coating of the walls revealed the existence of immured vessels or empty receptacles, which were completely undetectable at the prior state of the monuments. Typical examples are the vessels discovered in the katholicon of Halepa Monastery and the neighboring Agia Marina, in the katholikon of the Asomaton Monastery, in Agios Nikolaos in the village of Apostoloi, in the homonymous church in Lampiotes (prefecture of Rethymnon). Also in other cases, as in the Holy Apostles in Petrohori or the Assumption in the village of Aimonas (prefecture of Rethymnon), prior to the relevant actions of cleansing the churches, the vessels were completely whitewashed. In several cases, the final catalogue of the monuments of each region resulted after field research conducted by the project coordinator in collaboration with the colleagues of the Ephorates, since during the research additional monuments with examples of this practice were frequently identified. Typical is the case in the prefecture of Rethymnon, where 15 churches were originally located and now there are 70 churches identified with immured vessels on their façades.
During each fieldwork an effort was made for the most possible detailed documentation of vessels. Apart from taking detailed photographs with digital high-resolution camera, the diameter of the vessels or of the empty receptacles was also recorded. In some cases it was possible to imprint their profile, without physical evidence for the thickness of the parts of the vessel, given that their removal from the wall was not possible. In selected cases imprints of the façades of the churches were made, always in scale, in order to better highlight the position of the immured vessels across the façade of the monument, and for the layout of the vessels to become clearer as well as their relationship to other forms of decoration.
The second stage consisted in selecting the best photographs so that they could fuel the database, as well as the detailed documentation within the database of the monuments and the vessels of each region. In most cases the description of the vessels and the juxtaposition of the comparable objects was made by the coordinator of the programme, while in some cases the documentation of the vessels was made by the colleagues of the Ephorates in collaboration with the coordinator. The detailed documentation of the respective monuments was done exclusively by the cooperating with the programme archaeologists of the relevant Ephorates. An attempt was made for the most possible exhaustive listing of the bibliography related to the monuments or the vessels, so that the user can refer to it.