I believe the blade is dated Showa 18 (1943) and signed Mitsu ____ (can't make out the second Kanji - possibly "masa"). Likely a blade made in one of the larger Seki factories. Any arsenal marks on the tang?
Rich S
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Richard Stein, PhD
Old Puukkophile
NKCA Life Member
Japanese Sword Guide
http://home.earthlink.net/~steinrl/nihonto.htm
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