#301 is ink stamped under lacquer Kitsuyama Awasedo. Kitsuyama mine was in the SW portion of Narutaki machi (neighborhood) area of Kyoto. This mine-find is a rare stone from an obscure and short lived Showa period mining operation. 
Kizuyama mining complex was alongside Road #29 in the hills above the Utano Youth Hostel. 
In the size of 143 x 82 x 18mm thick it was set up for small tools but will generously accommodate larger western straight razors. Mohs 3 to 3+ a wide variety of steel will match well. There are no inclusions in this stone.
All of my stones are sold along with a tested tomonagura slurry stone, and a one month money back guarantee. Please don't hesitate to ask any questions.