This is a commemorative sake cup celebrating the Emperor's reign. It is a commemorative item produced to celebrate the 50th year of Emperor Showa's reign. The lid of the wooden box is engraved with the Imperial chrysanthemum crest and the words "Emperor's 50th Anniversary of Reign Commemorative Sake Cup." This commemorative item was made in 1976 (Showa 51), the 50th year since Emperor Showa ascended the throne. The back is marked 24K GP, so it is not pure gold and is for ornamental purposes. Please understand based on the photos. Thank you.