This is a temporal mule that’s also a transitional mule.  This bimetallic planchet was found in a 1992 St. Petersburg mint set.  The planchet was supposed to carry a 50 roubles design bearing the date 1992.  While it carries the proper design for this denomination, it shows the date 1993.  The 1993, 50 roubles is supposed to be struck on a solid aluminum-bronze planchet.

Someone at the St. Petersburg mint evidently grabbed from storage a reverse die intended for use the following year.
We suspect this was accidental.  The die was then used to strike the proper planchet for 1992.  Around 50 similar errors are known from other St. Petersburg mint sets released the same year.