230mm x 80-40mm x 35mm thick
CLICK PHOTO TO
ENLARGE
ENLARGE
KARASU tennen toishi are rare in and of themselves, and are exceedingly scarce
with the solid bold pattering found on this example. The living edge sides flare out
to create a solid base that is 90mm wide and tapers to 60mm wide, while the top
surface is a generous 230mm long by 80mm and tapers to 40mm wide. The side of
the stone is marked in ink Oozuku, a mine very near Nakayama. I cannot attest
that this is actually from the Oozuku mine but judging from the skin I believe it is
actually a Nakayama stone.
This is a very, very hard stone with the finest imaginable grit occurring in a
naturally mined stone. This karasu can be used with a nagura stone, a diamond
nagura*, or with just clear water as a final honing stone for plane blades, chisels or
as are popular in Japan as a barber hone.
A fugitive type stone, Karasu is found in the Aisa strata which is a deeply
compressed layer in the mines around Mt. Atago. Karasu is believed to be a name
ascribed by the early miners to these black pattern stones as representing "flying
crows". The minerals comprised in Karasu are, along with the dominate chert type
quartz, a concentration of mica which gives the black contrasts. True Karasu toishi
are not small pinpoint specks of mica but are instead these bold, blotchy or wispy
deposits with graphic imagery.
* Diamond Nagura is the use of a diamond plate to raise a slurry composed of the
host stones own grit particles.
with the solid bold pattering found on this example. The living edge sides flare out
to create a solid base that is 90mm wide and tapers to 60mm wide, while the top
surface is a generous 230mm long by 80mm and tapers to 40mm wide. The side of
the stone is marked in ink Oozuku, a mine very near Nakayama. I cannot attest
that this is actually from the Oozuku mine but judging from the skin I believe it is
actually a Nakayama stone.
This is a very, very hard stone with the finest imaginable grit occurring in a
naturally mined stone. This karasu can be used with a nagura stone, a diamond
nagura*, or with just clear water as a final honing stone for plane blades, chisels or
as are popular in Japan as a barber hone.
A fugitive type stone, Karasu is found in the Aisa strata which is a deeply
compressed layer in the mines around Mt. Atago. Karasu is believed to be a name
ascribed by the early miners to these black pattern stones as representing "flying
crows". The minerals comprised in Karasu are, along with the dominate chert type
quartz, a concentration of mica which gives the black contrasts. True Karasu toishi
are not small pinpoint specks of mica but are instead these bold, blotchy or wispy
deposits with graphic imagery.
* Diamond Nagura is the use of a diamond plate to raise a slurry composed of the
host stones own grit particles.
KARASU TENNEN TOISHI
Hardness Grit Speed/Strenght Price in U.S. $
10/10 10/10 8/10 w/DN or Nagura 10-/10 $1600
10/10 10/10 8/10 w/DN or Nagura 10-/10 $1600
HOME
STONESHOP
ARCHIVES
STEEL
LINKS
WOOD
TESTIMONALS
STONEGRADE
TOISHI
BOOKS
ARTICLES
KEZUROUKAI
DOCUMENTS
SHARPVSSHINY
TOISHI_DONTS
KANNA_SETUP
NOTES1
PARTS OF
A KANNA
