New genuine Nakayama?

[Fikira]

Hi there!

I'm the very happy new owner of a tennen toishi, and it's really great!

I bought it as a "Nakayama" and I was wondering if this stone has typical features of a Nakayama,
like the kawa / skin? I can only show bits and pieces of the side kawa...
I couldn't see the bottom because it's attached to wood,

Also, does anyone know what is written on the bottom? There are 3 lines, the last one is captured in 3 different pics

Thanks!