Mongolian Dollars were issued between 1921 to 1925. Treasury notes were issued under Baron Ungern in 1921, the denominations were 10, 20, 50 and 100 dollars. It was intended to replace the Chinese Yuan at par. Further banknotes were printed in 1924 in denomination of 50 cents, 1, 3, 5, 10 and 25 dollars however they were not issued to mourn the death of their Spiritual Head and Monarch Bodg Khan. The following year, the dollar together with other currencies was replaced by the tögrög in 1925. These unissued 1924 Treasury Notes are considered by collectors as the most collectable and are valued by collectors who priced them for their scarcity, rarity and their beauty in designs. References http://www.numismondo.com/pm/mng/index1.htm http://en.wikipedia.org/wiki/Bogd_Khan