Lot 20127 – 1898 (Oct 19). Commercial envelope from San Juan sent locally to Arroyo, U.S.- Puerto Rico mixed franking

1898 (Oct 19). Commercial envelope from San Juan sent locally to Arroyo, franked by 2c in mixed franking with Puerto Rico 1898 2c & 3c (round corner at upper left), all tied by « MIL. ST./SAN JUAN/P. R. » provisional railway duplex cancel, with receiving Military Station No. 1 bs, some toning and tear affecting the Puerto Rico 2c at top left; a very rare U.S. and Spanish stamps combination franking (described by AIEP Francisco Graus in the certificate as « of exceptional rarity »), one day after the turnover from Spain to the U.S.; cert. Graus (1990).