Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_31381 ( "Value" text, "Dimensions" text, "Main Color" text, "Obverse" text, "Reverse" text, "Watermark" text, "Date of issue" text )

### Question ###
How many different dates of issue are the for the coin with kumsusan memorial palace on the obverse?

### Accurate SQL ###

SELECT COUNT("Date of issue") FROM table_31381 WHERE "Obverse" = 'Kumsusan Memorial Palace'