By decree of January 11, 1866, the National Post Office was authorized to print and issue postal securities that were used as paper currency due to the lack of coins. These "billetes" were printed using postage stamp clichés.
After the arrival of the copper coin minted in France and England in June 1869, these paper money stamps began to be withdrawn from circulation.
They carry cancellations of the general accounting office of the nation.However, the catalog shows a copy with postal postmark, which makes intuit its use for postal purposes.
PAPER VARIETY.