When we talk about documents from the Middle Ages, such as international contracts, ruler’s decrees, state and private correspondence, we imagine a piece of string or ribbon stamped by red wax or metal seal.  The stamp strongly and clearly marked who edited the document and what his rank was. And the whiteness of the metal showed the importance of the diploma and even gave its name – hrisovuls /gold/, argirovuls /silver/, molivdovuls /lead/. The kerovuls which were made of wax were more popular in West Europe, but East people also used this practice. These unique bearers of information show us the career of different historic persons and their official or private contacts. They often enrich or correct the information for stories, which we know from the mediaeval historians.

     Archaeological museum “Veliki Preslav” owns the world biggest collection of lead seals, found on its archaeological context. There are more than 500 seals, dated back to the time of 9th to the end of 11th c. Most of them as well as cores of seals and ceramic moulds were found in the ruins of a big building in the Inner Town. They belong to Byzantine governors from 971 to 1088 when Preslav was a major city (Strategy) of the district.

     In addition to the collection, there are also seals of Bulgarian and Byzantine rulers and dignitaries’ seals. They were found both in the Inner and Outer Towns of Preslav, as well as in its nearby and distant surroundings. The finds are evidences of the regular correspondence between the Bulgarian and Byzantine courts, but also of the importance of Preslav like second political and strategic center during the time of its precapital period.