Originally Posted by
jnats
Many newer stock shobu are inclusion prone. Narutaki is fantastic, located about a kilometer from Nakayama. Old ozuku are fantastic, the newer stock hard ozuku are scratchier and leave a more aggressive edge. Harsh is terms of jnats, though still much smoother and healthier than a Gok 20k. Narutaki supplied a lot of surgeons stones as did Nakayama- which of course was tier 1 for the emperors samurai, and later temple carpenters. There are great Ozaki, Okudo (kiita and asia layers mostly though suita and asagi layers there also lent well to some fantastic razor stones) Narutaki and some old stock ozuku are going to be the bulk makeup of what will give you the sharpest edges. Some Nakayama are sharper- but more importantly, Nakayama razor quality characteristics are much smoother and more refined edges- the best formed edges along with Narutaki, under a scope and by way of edge retention. Third would be honing directly on a hone made up of Asano mikawa Koma nagura. These are generalities, as each stone is different, but working with stones from all the best mines, these are high frequency observations.