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 authorised 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 internationally popular sizes, such as the half gram of gold mini-coin format.
This coin is part of CIT's Lunar Year Collection dedicated to the Chinese Zodiac, and was issued to mark the 2018 Year of the Dog.
The Mint says about it:
According to the ancient Chinese zodiac, human character is interpreted not by the month, but rather by the lunar year of birth. This zodiac is represented by one of twelve animals. People who are born in the year of the dog are perceived to be honest, loyal, smart, and friendly. | 
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