5 lats coin coins were never minted as the Second World War broke out. After the Soviet occupation of Latvia in 1940, lats continued to circulate alongside the Soviet ruble, although silver coins had largely disappeared from circulation. (Even prior to the war, Latvian people had started to hoard silver coins to prepare for the imminent crisis.) On 25 March 1941, all denominations of lats were abruptly annulled. As the general society was given no prior warning, an estimated 50 million lats were never exchanged for rubles. The people were left with suddenly-worthless coins and bills, except for sentimental value and the silver
Currency mostly paper, but Australia's Commonwealth Scientific and Industrial Research Organisation developed the world's first polymer currency in the 1980s that went into circulation on the nation's bicentenary in 1988. Now used in some 22 countries (over 40 if counting commemorative issues), polymer currency dramatically improves the life span of banknotes and prevents counterfeiting. Currency use is based on the concept of lex monetae; that a sovereign state decides which currency it shall use. Currently, the International Organization for Standardization has introduced a three-letter system of codes (ISO 4217) to define currency (as opposed to simple names or currency signs), in