Japanese Sword Markings

Japanese sword markings are very significant in identifying an authentic Japanese sword. The age and value of antique Japanese swords are also determined through file marks that are etched on the tang. Other marks on Japanese swords like creative carvings add beauty to the blade while a blood groove improves the weight and balance of the sword. This article will help you learn more about sword markings, their types, and their purpose.
The Japanese sword markings:
1. Sword tang markings
a) File markings
Japanese file markings are etched on the tang (nakago) of the Japanese sword blade. They would vary in designs, depth, thickness, and spacing – all of which depend on the sword smith, sword making school, and the time the sword was made. Tools in marking may include a chisel, a hammer, and a plane used for shaving iron steel.
b) Signature
Japanese characters (Kanji) are also engraved on the sword blade. These characters are signatures of the sword smith who made the Japanese sword or the name of the sword owner. Most signatures are carved on the tang while some are etched on the base part of the blade.
Signed swords, especially signed antique Japanese swords can be expensive depending on the age of the sword and whose name was engraved on the blade. According to the Japanese sword history, the oldest recorded signed blade was a tachi (an ancient Japanese long sword) which was forged by Sanjo Munechika of the Heian Period.
2. Temper lines on the sword blade (Hamon)
The hamon is that pattern of lines on the sword blade which appears after the heat tempering process. This is created by applying a thick clay coating on the body of the blade and a thinner coating on the sharp edge before the sword is heated and quenched in water.
There are several types of hamon and a few of them are:
a) Suguha – straight line
b) Gunome – regular waves or loops
c) Sanbon-sugi – literally means “three cedars”; it displays cone-shaped waves that look like three cedar trees
3. Temper line on the tip (Boshi)
The temper line on the tip (kissaki) of a Japanese sword is called boshi. Like the lines on the sword blade, there are also different types of boshi patterns; for example:
a) Ko-maru – the temper pattern follows the shape of the kissaki part of the sword but forms a small arc when it reaches the back end portion of the tip.
b) Sansaku boshi – the temper line enters the point area and follows a straight outline until the tip of the point.
c) Midare-komi – a very irregular pattern
4. Blood groves (Hi)
A blood groove or fuller (hi) is a narrow channel found near the spine of a Japanese sword blade. This marking on Japanese swords is made by scraping off steel (with a plane or a chisel) from that portion of the blade.
According to some myths, grooves are created so that blood will flow from a stabbed person while some people say that blood grooves are made purely for decorative purposes. Both statements are not true.
A fuller is not made to let blood flow from the enemy. It is created to lessen the weight of the Japanese sword and improve sword balance, speed, and cutting ability.
Types of grooves:
a) Bo-hi – a thick straight groove
b) Bo-hi with soe bi – a large straight groove with a smaller and thinner line beside it
c) Bo-hi with Tsure-bi – also a large groove accompanied by a thinner but longer line beside it. The thinner groove curves as it passes by the end of the bigger groove and reaches spine of the blade.
d) Futasuji-bi – two parallel grooves of different lengths
5. Artistic carvings (Horimono)
Artistic carvings on the Japanese sword blade are called horimono. Traditionally, they had a religious and ritualistic background as the designs of these carvings were deities, Sanskrit characters in Buddhism, and mythical creatures like dragons. Antique Japanese swords with horimono were usually used as ceremonial swords.