The molyvdovoulla or voulles are lead seals or seals in general, used by the Byzantines ensuring confidentiality in their correspondence. They are valuable direct historical sources, and contribute to the study of the administrative system of the Byzantine Empire and the church hierarchy.
The collection of the Museum of Byzantine Culture, small but significant, comprises archaeological finds from Thessaloniki, Pieria and Rentina, purchases from the former collection Zakos, and donations from the Tsolozidis collection, the Economopoulos collection and by Demetrios Portolos. It numbers 100 seals, most of which are exhibited in the gallery "From Iconoclasm to the splendor of the Macedonian and Komneni" and the room "The twilight of Byzantium."
Comprises seals of emperors, patriarchs and church dignitaries, government and military officials, members of the aristocracy, private people and even anonymous ones.
Imperial seals occupy a special place in the collection. The seal of Tiberius II (698-705) (Fig. 1) and that of Constantine VII (913-959) are exquisite samples of the imperial portraiture.
Another important group of the collection are the patriarchal seals. The seals of the Patriarch Photios (858-886) (Fig. 2) and Michael Keroularios (1043-1059) stand out.
The church officials, the senior and junior clergy, are represented by a significant body of seals found in the upper floor of Hagia Sophia in Thessaloniki during the restoration works carried out after the earthquake of 1978, giving valuable information for the church of Thessaloniki.
The private seals of members of aristocratic families stand out for their large size and their good quality. A significant seal of Isaakios Komninodoukas (1180) (Fig. 3) was unearthed in the castle of Platamonas, and in Pydna, Pieria the seal of Alexios Komnenos Palaeologos.
An important part of the collection comprise seals of officials of the public and military imperial administration, as katepano, generals, magister, dukes, as well as officials of the personal guard of the emperor like, spatharioi, protospatharioi and spatharokandidatoi.