Definition of Sori
It is the designation for the curvature of the blade. A rough distinction is made between a rather strong and a rather slight curvature. To measure it precisely, a straight line is drawn from the outer end of the blade spine to the end of the sword tip and then measured at a 90 degree angle to the furthest point of the blade.
There are classifications according to the position of this vertex:
Torii
In this type, the apex is approximately in the centre of the blade
Koshi
Kashi Sori is used when the apex is shifted towards the handle.
Saki
This is the name when the apex is shifted towards the tip of the blade.
You can find more interesting articles about other components of the samurai sword in our article category Components of the samurai sword.
