The seals published on monasterium.net represent the result of an editorial project of The National Archives Branch of Harghita County in cooperation with Miercurea Ciuc Municipal Hall and Csíkszereda Publishing: Crini, Coroane, Lebede. Coleccția de sigilii a Arhivelor Naționale Harghita (Bicsok Zoltán, Editura Csíkszereda, 2015). This bilingual published material analyzes 225 representative seals of the „Colecția de sigilii a Muzeului din Cristuru Secuiesc” (The Collection of Cristuru Secuiesc Museum’s Seals), in total amount of 1303 pieces which had been entirely digitized. The collection was born by the pasion and determination of Sándor Mike [de Turia de Jos] (1795-1867), archivist and genealogist, and József Kemény, conte de Mănăstireni (1795-1855), historian, both of them accomplishing a great achivement in this scientific field. Since the middle of XIXth Century, after the death of the owners, it had been preserved by the Library of the Unitarian Gymnasium in Cristuru Secuiesc (Székelykeresztúr, Kreuz), later, by the local museum, and finally, since 1970’s, by the National Archives in Miercurea Ciuc. The seals, divided in 4 categories – royal seals, seals of administration, seals of private institutions and personal/familial seals, provide a substantial source of information for researchers (historians - sigillographers, genealogists, archivists) not only on Transylvanian level, but European one, and they are now – part of them, at least – available online.