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  • Writer's pictureALEX

A peak into the past and the future regarding Jnats

Posted on December 26, 2012

In the past few years I have noticed a large influx of hard gray stones marked Oozuko (Ozuko) flooding the U.S. market that have come from one particular wholesaler in Kyoto. Although the Ozuko mine has been closed for 90 years these stones appear to be newly slabbed and freshly ink stamped (Ozuko never stamped their stones) and then retailed to the various blade forum members by one particular retailer/importer. This influx of stone just so happened to coincide with the recent English translation of Honing Razors and Nihon Kamisori , a booklet written in the 1950’s for the Japanese Barber Trades by the renowned blacksmith Iwasaki Kousuki of Sanjo.

At the time when Iwasaki-san wrote his pamphlet for the barber school, the most famous of all the awasedo bearing mines, the Nakayama was just then digging their last tunnels for extraction. All of the other major and famous mines had closed some 50 years earlier, but still Iwasaki-sans greater interest was in providing the barbers of Japan reliable information and a sharpening system that could be duplicated and used and taught within the trade in order that consistent and excellent results could be obtained in honing razors. Iwasaki-san was a scientist in his own right and he followed and was familiar with following reasoned and well thought out procedures. He chose to use natural stones because there were not, as of yet, any man-made synthetic stones to rival the naturals, and because all barbers did still use and have in possession some form of domestic razor hones which they were still using.

I do firmly believe that Iwasaki-san was truly genuine in his effort to promote good sharpening for the barber trades, and during this period he worked closely with Kato-san the owner at the time of Nakayama Mine in selecting the best grade of stone that would suit razors in conjunction with the use of white Aichi Mikawa nagura. At this same time, Iwasaki-san was encouraging the principal owners of the Aichi mines to reopen their mine so in order to produce the white nagura again that would work in harmony with the Nakayama stones; and to develop a grading system for the nagura just as Kato-san was doing designing and stamping a Kamisori Nakayama Toishi base stone. The Nakayama stones suggested were gray and hard and readily available, the Aichi were white and soft and the Iwasaki system works reliably well with some instruction while using those particular stones.

The only problem however that Iwasaki-san failed to realize is that both the Aichi mines and the Nakayama mines were destined to close within the next generation, so that here we are now currently in 2013 with the original sources of these top quality stones dried up.

A limited number but not all of the ancient mines right in the heart of the Yamashiro District did in their time produce razor grade stones or what is called in Japan kamisori toishi, but the quota was always small. I have been told by the retired mine owner Yamamoto-san that: out of an honest ton of raw stone found in the thick & rich veins of the mines at their peak, only 10% was useable for sharpening; with 99.9% of that ten percent dedicated for tools like chisels and hand planes; and only 1% of that ten percent suitable for razors. In other words if my math is correct, only 0.01 % of the total tonnage is suitable for razors.

The recent marketing in Japan of alternate stones (those not selected by Iwasaki for kamisori purposes) by the wholesalers has been a windfall in Kyoto. Every miner and wholesaler has had in and still does have in storage lockers of thousands of tons of ultra hard stones that are now, in Europe and the U.S., referred to as level 5+++ hardness, and touted by evolving retailers. These very, very hard stones had never been popular in Japan because of their difficulty in use and their slow cutting abilities. They were referred to as “scratchy stones” or only for “experienced sharpeners”. There are still to be found in stores and storerooms but in very limited sizes some of those faster cutting but more expensive stones, but these ultra quality stones are not openly out on the shelves for the hobbyist or casual purchase, but are instead reserved for the master craftsperson or the generational favor-ism show to repeated customers of long standing and kept in the back rooms where tea is served with dainty cakes. Some times really great stones are gifted as a gratuity or ex gratia honorarium to esteemed craftspeople like famous mia daiku (tea house carpenters) of the highest order or national recognition, or believe it or not gifts of such are even not accepted by the Imperial Family.

No, it is these monolithic, ultra hard, gray stones, leftovers from better times, dusted in cold storage until these fruitful days came when they were “discovered” by western razor users, to whom had few alternate Jnat stones as comparisons or alternatives. But don’t fret, there are ways to still use them.

These fairly priced and relatively inexpensive highly compacted stones came from the tunnels dug at lowest elevations of the mountain side mines, some even from within the depths of the local water table. You see historically the first stones were discovered near the mountain crests and over the past 800 years these mineral rich deposits were dug out at ever and ever lower elevations as the shallow vein layer was followed and played out above in the earlier tunnels. By the turn of the 20th century all of the mines had depleted the upper regions and as a last ditch effort a few mines even dug below the water table. For the first time in the history of these famous mines they needed to use water pumps in order to work in the mines. The Narutaki mine was even dug out with steam shovels, dynamite and bulldozers below level ground. There is a published photo of Kato-san in a mine shaft wearing sailor type full rain gear with hat and boots attempting to remove stone with water sifting in from above like rain. The Nakayama stones from this elevation are specially stamped in ink with the logo of a block and tackle pulley to represent that the stone had to be lifted up and out of the mine. This was the very last dig for the Nakayama.

At these, the lowest elevations, the mineral make-up of the awasedo strata were not only ultra hard because of the full bearing weight of the mountains compaction upon them, but also transmuted as the integral water soluble minerals that make up the clay binders in Hon Yama awasedo had been dissolved and squeezed out millions of years ago leaving a harder more condensed silica mass minus the clays. What was left behind at these elevations below the mountain wallowing in the wet ground was just hard gray mass with little in common to the unique characteristic stones that were mined from above.

The situation recently here in the U.S. is that the Iwasaki system as easy and beautiful as it is was developed nearly 70 years ago, has at its core the now rare and various white Aichi nagura stones. The nagura portion of the system has developed into a have or have not dilemma with the purer pieces of Mikawa Aichi nagura harder to buy and more expensive. At the other end of the system, because of the moderate historical experience of razor users using Jnat natural stones in the U.S., there are fewer out there judging intrinsic qualities of Nakayama or any of the other major closed up mine stone by other than what is laid out before them in sales brochures.

What has overtaken the current razor honing culture here in the U.S., encouraging a following of Jnat users who have not been exposed to other types of rare stones that were predominately used in Japan previous was, the Iwasaki’s system. It should be noted that before 1955 the tens of thousands of barbers in Japan were using a very wide range of stones for razors with great success, and had been for several hundreds of years. These kamisori toishi being smaller were often set on wooden bases for stability and used until very thin, were chosen first for their character and abilities including their cutting speed and fineness of grit; and more often then not were of medium to medium hard composition. The slurry stones I have found in old barber shops in rural Japan were often a similar stone, usually rounded like a short cigar and always cherished. A barber in the old days who lived a day by horse or two by foot to the nearest small town did not use white Aichi Asano red ink stamped nagura. They used a small piece of a similar Hon Yama (original mountain) stone that was somewhat softer but was of still of equal grit character and quality.

I believe that Iwasaki-san in his wisdom and concern saw the end of the line for the supply of the very unique stones, and chose, designed and dedicated for razor use along with Kato-san a complete system that could use the lovely fairly hard stones, while all the time thinking that the source of Aichi nagura and hard gray stones would last maybe a few more lifetimes into the next, now current, century. Again there is no fault here on their part if my intuition is true, they were keen on providing a needed service and system to the greater good of professional barbers.

The saving grace here, and all hope is not lost although it can be a hard nut to swallow for some, is the invention of the Diamond Nagura which I will speak of next.


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