Two proposed designs for this medal.
Published (May 24, 1887) original regulation.
The obverse reads
褒章 - Medal of Honour
reverse
賛成防海事業 - For donation [support of] to naval defense
A donation of 5 000 yen made one eligible for the Silver medal.
10 000 yen donation would get him a Gold one.
Between July 20, 1887 and January 10, 1894 (when the last medal was awarded) a total of 572 silver and 54 gold medals were awarded.
The exact number of minted medals is not known.
Curiously the medal was officially abolished only on May 3, 1947 by Cabinet Order No. 4.