This is an antique Japanese military tea cup, decorated with a star and the words "Army Officer Academy". In English this school is known as the Imperial Japanese Army Academy. There's a maker's mark at the bottom of the cup. The style and make quality of the cup suggests this is probably a post-war production - most likely for veterans who used to teach/work at the academy in a get together.

Condition: Mint

Size: 3" tall x 2.5" across