02-21-2021 09:11 AM
02-21-2021 09:23 AM - edited 02-21-2021 09:27 AM
The mark is a bit fuzzy, but I think it is Tecuka.
Go here, and scroll down to Tecuka, Mark #1342:
http://www.gotheborg.com/marks/20thcenturyjapan.shtml
02-21-2021 09:28 AM
It is Japanese. The characters in red are in katakana: テツカ.
02-21-2021 09:42 AM - edited 02-21-2021 09:46 AM
Here are OP's mark and the mark from Gotheborg, to compare. I think they're the same, don't you?
02-21-2021 09:54 AM
Yes, mine was a cross-post, sorry.