Some examples of the great makers' flutes on display at the Hamamatsu Museum in the Shizuoka prefecture in Yushin's vicinity.
There were several classifications that Taizan stamped into Kogetsu's shakuhachi.
"Tofuku Myoan Taizan" was the highest rank.
"Myoan Taizan" was the middle rank.
"Taizan" was the lowest rank.
The rarest and most valued shakuhachi have the "Tofuku Myoan Taizan" stamp with illustrations and sometimes Chinese kanji, too.
The following photos are of the rarest and valued classification of Kogetsu antique shakuhachi, one of which was sold on a Japanese Yahoo auction last year 2010.
The Kogestu Hanko
Two examples of authenticated Kogetsu hanko collected by Dr. Inagaki. He owned a great number of rare jinashi, many of which after his passing were sold to the musical instrument museum.
From John Singer's website; "Kogetsu Hayashi was the leading Myoan maker of his time. This extremely rare shakuhachi is one of his best instruments. It has great body and clarity of tone. The balance and ease of response are superb. Higuchi Taizan (founder of the current Myoan style) used instruments made by Kogetsu. (Private collection)."
An example of a conterfeit Kogetsu hanko!
An example of a hanko that is possibly fake.
Another example of a possibly fake Kogetsu hanko.
Kogetsu also used two other hanko early in his career:
秋草 Autumn Grass
水辺 Water Wedge