Need help with mei ID-ing

[TomHT]

Came across a blade that has this unique mei. Any help in ID-ing it would be greatly appreciated. Thanks!

[SteveM]

古極？　Old attribution of ? 　正？延？

[k morita]

Hi,

The Mei says 吉明作 (Yoshiaki saku).

Maybe this sword was made in late Edo period.

He was Gassan school.

[k morita]

Hi,