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 the third release in the Evolution of Life collection, and features the Ichthyosaur.
The series features select fossils from various geologic periods, in one large silver and one small gold format. Each silver issue shows a rose-gold plated fossil, typical of the respective geological period, partially excavated on an antique finish rock matrix background. The gold coin motifs mirror those of the larger silver coins, if in reduced complexity and design. Instead of a partially excavated fossil on a rock matrix background, the little coins show the isolated fossil on a proof surface with English name, year of issue and series name. Despite their small size, their minting is incredibly rich in detail.
The mint says about this coin:
New issues of the Evolution of Life collection are one of the most anticipated CIT coins at the yearly ANA show. The astonishing and detailed high relief fossils, plated in rose gold and set in an antique finish matrix, have garnered a huge following among coin collectors. After lingering in the Paleozoic Era for two years, the series now presents the Ichthyosaur of the Mesozoic Era - the Age of Reptiles. The Ichthyosaur fossil is covered in rose-gold while the smartminting relief accentuates the bony scleral eye ring and pointy teeth of this Triassic predator. Ichthyosaurs were marine reptiles that lived 250 to 90 million years ago. The various species resembled modern dolphins by convergent evolution or the development of similar traits in similar environments. | 
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