I found this Italian 1 Lira accidentally mixed in with my modern "junk" coin bin. Probably got it for 10 or 25 cents and didn't notice it was from the 20s. Anyway, I thought it was cool that it had a "good for" coinage clause similar to the French post-WW1 base metal coinage. The price of silver shot up during WW1 and the early 1920s. Most countries were on a gold standard at the time, but many suspended convertibility of paper money to gold during the war. The resulting inflation showed up in the price of silver. Money which had been "token" silver (less metal value than face value) suddenly was worth much more as melt and stopped circulating. I guess both France and Italy issued base metal 1 franc and 1 lira coins to deal with this problem. They didn't want to call this a permanent debasement, so added the "good for" clause on the coins to indicate it was a temporary measure. For similar reasons, the UK had to drop the long-held 92.5% sterling silver standard for its coinage down to 50% in 1920. Anything much higher purity simply wouldn't have circulated in 1920. German notgeld and kreigsgeld circulated for similar reasons (though Germany also had an inflation crisis in the early 1920s). If you like, please post any coins from this period (about 1915-1925). Any silver coin denomination which was formerly more than about half of face value's worth of metal would have been affected.
