Attributions are always, at best, an educated guess based on a person's
knowledge and research. With Japanese swords, there is an expert
panel (Shinsa team) with a zillion years of examining, handling, researching,
etc. some of the best and widest variety of Japanese swords in existence;
however, sometimes they still get it wrong. Submit a sword for shinsa to
one team and get an attribution. Submit it to another team and you may
(not uncommonly) get a different attribution. If a blade doesn't jump out
as say "I'm a ......" , then it's a best guess which may be right or wrong
and may very well change over time as we gather more knowledge and
experience.
Rich
The Japanese Sword Index
http://www.geocities.com/alchemyst/nihonto.htm
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