Tanto originally no-signature
Blade length 29.1cm, thickness at the base 6mm, width 2.5cm
This is a nice tanto blade without signature. But the blade character clearly illustrate Mono tradition in the age 15-16th century. The file mark doesn't match to the style of Seki smiths. So probably some smith in Mino province except for Seki city.
Steel is fine, and it has a wood grain layer pattern.
Hamon is very bright, made of small particles and large particles.
Polishing work is sashikomi style or very soft hadori. Anyway no acid, and it is very clear probably because of many years treatment. It brings up the beauty of the blade honestly.
Tang
We don't know why originally no signature on such a nice blade. => Why originally no signature
Habaki is gold foiled.
Shirasaya and bag
It is a little bit weary, but still shows what good quality blade is. You can study the fine steel and bright hamon.