Anybody have stones from Maruoyama? Would be interesting
to learn about heir hardness, finess etc.. how they perform.
They have all type of stones from different stratas.The owner of the mine
has a website : 天然砥石採掘・販売　砥取家（ととりや）【京都・亀岡 】.

Their stones are usually for knife and plane blade sharpening. but
they now sell stones specifically for kamisori. This is the Kanji:
大谷山 戸前浅黄 カミソリ砥(Ooyaniyama Tomae Asagi Kamisorido)

Sharpman