These stamps were issued as a set in 1980 and each stamp features the score of a Japanese song.
Date of Issue: 28th January 1980
Left: Mount Fuji, 50 yen
Right: Winter scene, 50 yen
The iStampGallery blog provides more details about the songs featured on these stamps.
I bought these stamps on eBay for 0.99 USD. Mount Fuji is one of my topics. It is also my favourite mountain. There are no other mountains on my list, so perhaps it is better to say that it is my favourite world view.