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 the Revolutionaries collection.
The Mint says about it:
To commemorate Cuban revolutionary and political leader Fidel Castro, who died on 25 November 2016, Mongolia has issued an appealing coin set with a classic design, minted with state-of-the-art technology. The design is based on the coin’s predecessors the Chinggis Khaan issues of 2014 and 2016. The gold coin presented alongside the silver issue nearly mirrors it in design. Thanks to CIT’s Big Gold Minting process, the size of the gold coin increased from 11 mm to 13.92 mm while at the same time retaining relief height and detail. | 
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