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 first release in the Evolution of Life collection, and features an Ammonite.
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.
While ammonites superficially resemble snails and nautilus, the marine creatures were however more closely related to octopus and squid. Gas-filled chambers within the shell allowed them to move up and down the water column in search of prey and to avoid predation by Mosasaurs. The striking, red-gilded reconstruction of a partially excavated Ammonite represents the Devonian Period which lasted from 419-359 million years ago. While fossils of the Ammonite’s head and tentacles are extremely rare, their shells are among the most abundant fossils and can in fact aid in determining the age of the rock they are found in. | 
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