This is a rare spanish silver coin. It is more than 200 years.
Only 6,000,006 were minted in Madrid, Spain according to the book of Aldo Basso entitled Coins, Medals and Tokens of the Philippines 1728-1974 2nd Edition (1975).
OBVERSE: Alfonso XIII P.L.G.D.D., Rey C. De Espana. The young head of Alfonso XIII is facing left, the date is between two five pointed stars.
REVERSE: Islas Filipinas/UN Peso. Crowned coat of arms between two pillars in the center.
By carefully observing the coin you will notice that this coin carries three sets of initials: on the obverse below the neck, B.M. which stands for Bartolome Maura Montaner, the die sinker; on the reverse, left edge, S.G. for Arturo Sandoval and Antonio Garcia Gonzales, the assayers; and right edge, V. for the weight master, Remigio Vega y Vega.