The currency of Mongolia since 1925 has been the tögrög, which currently circulates mostly as banknotes due to the low value of earlier coins and the reluctance of the government to issue large denomination coins; however, the government has authorises many non-circulating legal tender (NCLT) coins to be issued for collector's purposes.
Collector coins are dedicated to historical or general popular culture themes and are often not related to the country itself. Many of them are in standard bullion sizes, including the internationally popular one ounce of silver format.
This coin is part of CIT's Lunar Year Collection dedicated to the Chinese Zodiac, and was issued to mark the 2020 Year of the Mouse.
The Mint says about it:
The 12-year Chinese lunar earth cycle concluded in 2019 with the year of the pig. CIT celebrated the event with a superlative lunar coin, struck with smartminting technology, in the three-dimensional shape of a pig. The creative team of CIT managed to breathe new life into the crowded world of lunar coins that flood the numismatic market each year, and the success of the Jolly Silver Pig paved the way for its successor, ushering in the lunar metal cycle with the year of the mouse.
The Witty Silver Mouse issued for Mongolia is once again struck three-dimensionally, to produce a freestanding, adorable mouse that not only numismatists will come to cherish and adore. | 
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