The peso was the standard coin of the system Congress set up for the Philippine Islands by the act of March 2, 1903, which fixed it at half a United States dollar. Filipinos came to call it the Conant, after the monetary adviser Charles A. Conant. Melecio Figueroa designed the obverse, a Filipina with a hammer raised over an anvil and the volcano Mayon smoking in the distance; the reverse took the American arms, an eagle above a shield. Philadelphia struck pesos for circulation in 1903 and 1904 and proofs every year from 1903 to 1908; San Francisco struck the great majority of them.
Rising silver costs soon caught up with the heavy 26.95-gram peso. Congress answered on June 23, 1906 by allowing the islands' government to make its silver coins lighter and baser, provided the peso stayed at 70 percent silver or more. From 1907 the peso weighed 20 grams of 80 percent silver and measured 35 millimeters. San Francisco struck the reduced coin from 1907 to 1912, and then no more pesos were made for circulation under American rule.
The only later pesos are the two 1936 commemoratives from Manila, Ambrosio Morales's work, marking the new Commonwealth. They sold slowly. In May 1942, as Corregidor was about to fall, silver coins with a face value of millions of pesos were dumped into Caballo Bay to keep them from the Japanese, and many of the reduced pesos and unsold commemoratives went with them; much was salvaged after the war.
