1859 - Sardinia: 20c dark blue, first plate, print

 1859 - Sardinia: 20c dark blue, first plate, printing 59, from 'SOLERO 11 MAG. 1859' to Condes. Extremely rare earliest known use of a Sardinian stamp by French troops at reduced civilian rate during the Franco-Sardinian campaign of 1859. The letter was taxed on arrival, as only from 8 July would the regulation come into force allowing letters from French troops to France to benefit from the reduced 20-cent rate. Detailed cert. E.Diena (Sassone 15B - Euro -)