The Belarusian Rouble was introduced as the currency of Belarus in 1992, but the country initially issued no coins at all; circulation was served by banknotes instead.
In later years, Belarus became a large producer of commemorative coinage for the numismatic market, particularly gold and silver bullion coins and non-circulating legal tender. Their designs range from fairly commonplace to unique and innovative; themes range widely from "native culture and events" to fairy tales and pop culture topics not related to Belarus at all.
Large silver coins are issued in the "silver ounce" format and are usually denominated with a face value of 20 Roubles; between 2000 and 2016, these were of the "Secound Rouble" currency (ISO code BYR), which was demonetised after 2016 and replaced with the current "Third Rouble". The coins were issued at prices considerably higher than their intrinsic value, so are technically "Non-circulating Legal Tender" (NCLT) coins and not bullion.