Unicode中包含有多套数字系统，蒙古数字是其一。初看蒙古数字很正常，但是，有很多奇怪的地方。

相关资料非常少。我和Sure讨论和研究过蒙古数字的用法问题。我们的出了下面的结论——虽然我们并没有足够使人信服的证据。

蒙古数字与藏文数字有关，也许蒙文数字源于藏文数字。现在，蒙古数字仍然（或许仅仅）用于蒙古国的货币。

过去，蒙古数字可能用在老蒙文和托忒文的佛经中。明朝和清朝出版的老蒙文和满文的书籍的页码有时是用汉字数字（而非蒙古数字）书写的。

满文、锡伯文、达斡尔文中不使用蒙古数字。

蒙古字母的书写是从上到下竖写，然后从左到右换行。【竖排的中日文是从上到下竖写，然后从右到左换行。】而蒙文数字是从左到右横写。奇怪吧！

也许，老蒙文中并不使用蒙文数字吧？

Mysterious Mongolian Digits

There are several numeral systems encoded in Unicode including Mongolian digits. You may think that everything is normal with the ten Mongolian digits at first. But they are really mysterious.

There are nearly no materials about Mongolian digits. I have talked with Sure about the usage of Mongolian digits. We think the following point of view is correct tho we don't have a convincing proof.

Mongolian numerals are related to, and probably based on, the Tibetan numerals. They are still (maybe only) used on Mongolian tögrög banknotes.

They probably were used in Buddhist scripture rolls (Traditional Mongolian and Todo Mongolian versions) before. The page numbers of Mongolian and Manchu books published in Ming and Qing Dynasties were sometimes written in Chinese.

Manchu, Sibe, and Daur languages do not use Mongolian numerals.

Mongolian is written vertically from top to bottom, then from left to right (tb-lr). Chinese and Japanese were traditionally written vertically from top to bottom, then from right to left (tb-rl).But Mongolian numerals are written horizontally from left to right, then from top to bottom (lr-tb). (Mysterious!)

Maybe Mongolian numerals are never used in Mongolian text.