The red circle indicates the time we discuss in this section
Chukan-zori (中間反り) ————— Chukan-zori tanto has a straight Mune(back), its back does not curve forward or outward unlike Takenoko-zori, Chukan-zoridoes.
Hamon (刃文: Tempered line) ———–Sanbon-sugi (三本杉), O-notare (大湾), Yahazu-midare (矢筈乱), Hako-midare (箱乱), Gunome-choji (互の目丁子), Chu-suguha (中直刃) See below.
Horimono (彫り物: Carving) —————Often hi (grooves) is curved
Tanto Length ———————— The length of a tanto should be no longer than one shaku*¹ (approx. 12 inches, 30.5cm). The standard size tanto is called Jo-sun Tanto, which is 8.5 shaku (approx. 10 inches, 25.7cm). Longer than Jo-sun is called Sun-nobi Tanto (寸延). Shorter than Jo-sun is called Sun-zumari Tanto (寸詰).
Sun-nobi Tanto > Jo-sun Tanto (approx. 10 inches) > Sun-zumari Tanto
*¹ Shaku is a Japanese old measurement unit for length.
Takenoko-zori Jo-sun Tanto (筍反定寸短刀) ———– This type of tanto was made during the Sengoku period. It resembles the swords made by Rai Kunimitsu of Yamashiro Den. (Illustration below)
Hamon (刃文: Tempered line)———–Hoso-suguha (細直刃: Narrow straight hamon). Katai-ha (illustration below) shows somewhere on the blade. Masame–hada (Straight grain pattern) may appear on the mune side
Ji-hada (地肌: Area between shinogi and tempered line)——— Shirake (白け) whitish surface) sometimes appears. Uturi (the whitish light cloud-like effect) on Ji-hada appears.
Sun-nobi Tanto (寸延短刀)–———Tanto of this type is similar to the Sakizori tanto which is from the late Soshu Den style. You may see hitatsura (see below illustration). Unlike Soshu Den, the Hitatsura type hamon shows more on the lower part of the tanto, less on the upper part.
Hirazukuri Takenokozori Sunzumari Tanto (平造筍反寸延短刀)
This is a unique tanto in the Sengoku period. Hirazukuri means a flat surface sword without shinogi, yokote line, or obvious kissaki. Takenoko-zori means bamboo shoot shape (back of the sword curves inward). Sun-zumari means shorter than 10 inches long (shorter than 8.5 shaku, or 25.7 cm). The lower part of the blade is wide and thick, and the tip is narrow and thin. It has a piercing sharp look.
- Horimono(彫り物: Carving) ——-Deeply carved Ken-maki Ryu (a dragon wrapped around a spear).
- Hamon (刃文: Tempered line)———Wide tempered line, nioi base. Irregular hamon, wide suguha (straight) and Chu-suguha (medium straight). The hamon in the boshi area turns back long.
- Ji-hada (地肌)———–fine and wood burl pattern.
Moroha-Tanto (諸刃短刀: double-edged sword)
Double-edged blade with a hamon on both edges. Often bonji (Sanscrit) is curved.
- Hamon (刃文) ——— Wide tempered line. Nioi base. Irregular hamon, wide suguha (straight) and Chu-suguha (medium straight). Hamon turns back deep.
- Ji-hada (地鉄)——- Fine and wood burl.
Name of swordsmith during the Sengoku Period (Tanto maker)
The swords during the Sengoku period are called Sue-bizen sword. Bizen Osafune Yoso Zaemon Sukesada (与三左衛門祐定) is the most regarded swordsmith during the Sengoku period. He also forged tantos. One thing to point out is that there were many swordsmiths called Sukesada. Yoso-Zaemon Sukesada is, however, the one who represents the era.