Costa Rica’s monetary reform caused this 1903 50-centimos to be redenominated as a 1-colon piece in 1923. This silver piece (29mm, 10gr, .900) is the big brother of the Costa Rican counterstamp 0f 1887/1923 earlier in the thread.
These 1903 50-centimos pieces were struck at both San José and Philadelphia—the coins are said to be indistinguishable as to mint—and were among the 460,000 (
Krause says 421,810) Costa Rican 50-centavos and 50-centimos pieces dated between 1880 and 1918 to be employed as “host coins” for the 1923 1-colon pieces created by counterstamping.
How long these silver counterstamps remained in circulation I cannot say, but the first purpose-struck 1-colon pieces are the 350,000 copper-nickel coins minted at Philadelphia in 1936—but dated 1935.

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