That is quite a title. I'm not too sure if there were any other silver colored coins issued earlier but I reckon it may be true
Currently if you google which country issued the first circulated color coins, the title goes to Canada. However little did you know that there were coins issued that were manually enameled back in 1882-3!
You see, Korea was going through an era of currency reform where the public had serious issues trusting circulated coins. Coins at that time were cast coins. At that time, various government branches were actively culling good quality copper coins and melted down to produce cheaper bronze / brass cast coins creating massive profits. This devalued the value of the coins and the public was clearly not happy over it.
In 1882 - 3, an attempt was made to cast these coins in good quality silver. And to top this up, these had three different enamels at the reverse of the coins. 3 denominations were issued - 1, 2 and 3 chon and in three different colors - black, green and blue. I'm not sure if the colors mean any thing.
When released, this kinda did what it was meant to do... it was too popular with the rich and many were hoarded. This would be the first and final colored silver cast circulated coins for Korea. This would be the prelude to introducing machine struck coinage
Today these coin prices have gone through the roof and are somewhat difficult to find due to the novelty.
The three coins
1 chon (black enamel)
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2 chon (green enamel)
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3 chon (blue enamel)
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I was lucky to have them in different colors just by coincidence!
Hope you enjoyed reading