In the Treasury Tickets of the Kosciuszko Insurrection, unlike later issues of paper money, the serial numbering of individual pieces is carried out only numerically. The series letters seen on these bills are not linked to the number, but are the designation of the engraving plates. These hand-folded and hand-engraved plates differ in detail. Each series denotes a different plate, which means in practice a different banknote in terms of details. As a result, the letters of the Insurrection banknote series are something completely different, and more than what they become in later banknote issues. Completing the individual letters of the Insurrection banknote series means, in practice, completing prints from individual plates, where each plate has its own individual characteristics.
A beautiful piece from the rare C series (plates).
Banknote from the collection of Miroslaw Zbichorski, whose collection of excellent Insurrection banknotes is discussed in a dedicated video on Youtube.com/MarciniakTV.