1 Sen - Shōwa Not issued

Mt. Fuji on one side and the national Sakura plant on the other

Obverse
Sakura blossoms in the center
surrounded by three kanji at 4, 8 and 12 o'clock

Lettering: 本 日 大

Translation: Great Japan

Reverse
Upper left an accounting kanji, meaning one
in the backgraound Mt. Fuji with clouds

Lettering: 壹

Translation: 1

Edge
Smooth

Features
Country    Japan
Type    Standard circulation coin
Year    (1945)
Calendar    Japanese - Shōwa era
Value    1 Sen (0.01 JPY)
Metal    Red porcelain
Weight    0.8 g
Diameter    15 mm
Thickness    2.4 mm
Shape    Round
Demonetized    yes
References    KM# 110

Made by Kyowashinkou Porcelain Co. in Kyoto also Seto Co as an experimental coin at the end of world war 2.
60% Sankansaka Clay, 15% Granite, 15% Red clay and 10% other.
The most common non-issued porcelain coin to be seen. It is said to have circulated for a short time at the end of the war.