Ukubi type: thin back.
Shobu typc: ridge type, without sides, and with a thin back.
Plain type: some are bent and some straight; the cutting edge is termed fukura.
Short sword: 1. shaku (more than 12 inches) long.
Middle-sized sword: from 1.03 to 1.75 shaku in length; of the ridge type, etc.
Sword: more than two shaku in length.
Modified halberd: of various lengths.
Old Bizen: The smiths before the era of Genrei.
Kuitashi: from 1.05 to 1.95 shaku in length.
Great short sword: from 1.08 to 1.99 shaku in length.
Tashi: commander's sword of different forms but modeled upon the lines of bisection of the riken (double-edged lance point).
Kiriha: a sword with an edere like that of a small knife.
Kosorimono: works of Nagafune from the era of Aei to that of Eiwa.
The sword form is derived from the bisection of the hoken (leaf-shaped double edged lance form).
The "length" of a sword is the measure of the blade from the point to the hilt—the length of the nakago being disregarded.
The sword is composed of a highly tempered iron body to which a steel edge is welded. The best work has a white edge and blue body. "Middle" work shows a blue edge and black iron, and inferior blades, a black edge and white iron, although the nature of the metal must naturally differ according to country and the different methods of each swordsmith.
Jifu. The skin marks left by welding: they consist of regular or irregular woody lines, "pear-skin," etc. Its characteristics vary according to the province of the swordsmith.
Utsuri. Shadowy marks in the plain, sometimes in the whole of the blade, seen in the Bizen class, and especially in the work of Kanemitsu.
Works of the high ridge.
Mihara, Nio, Yamato class, etc.
Works of the wide furrow.
Miike, Yamato class, Kiyotsuna, Mitsutada, Unji, Sukezane.
Works of the thick back.
Yamato class, Yoshimitsu, Kagemitsu, Kagemasa, Miike, Nobukuni, Sa, Seiren, etc.
Works having decorations carved near the center of the blade.
Kunitsuna, Eanehira, Masatsune, Norimune, Ichimoji class, Naganitsu class, C'hikamura, Heianjo, Shiga class, etc.
Works having the round back.
Hasebe, Mihara, Miike, Masamune, Sukezane, Aoye, Kuniyashu, Nagamitsu, Kanahira, Tomonari, Nobukuni, Fuyuhiro, Nio, Kogawa, Kagashiro.
Works of the triangular back.
Also called "Shinno Mune " (true back), chiefly seen in the works of the Kyo, Yamato and Sagami classes.
"Cap" or point.
In the Yamato class it is closely welded. In the Seki class it is rounded, and in the Bizen class it is pointed. There are of course exceptions. In the Sagami class it is widely and strongly welded.
NIE (Boiling Mark).
This is sometimes seen on the plain, but its quantity and quality differ according to the work. Although it is characteristic of superior work, it is also seen in the inferior grades. The ' boiling' in the latter class is angular and crowded, besides being indistinct and dull, while the boiling mark of the superior grade resembles the finest lacquer surface, strewn with silver powder. This mark is seen either on the edge or the boundary of the welded edge. The ' welded back ' and ' Yubashiri' generally has the ' boiling,' and whether it is abundant or scanty, a bright boiling mark is regarded as the best.
Hazy rays pouring forth from the boundary of the edge to its margin and found in the superior grades, but not in the lower. Although it occurs in the middle grade, it is irregular and uneven, while the deep glory enclosing the boiling mark is seen only in the best work.
A brilliant woody texture differing both from sunagashi and from jifu, and seen only in the best grades.
Like jifu (see above), but more brilliant and glittering; seen chiefly in the boundary of the edges in the highest grades.
Something like the welded edge, fine NIE, and occurring here and there outside the edge.
A NIE (boiling mark) like strewn sand, occurring both on and about the edge.
This term has been used to describe small 'Yakiba' shapes in the JI. The translation is "running or boiling water." These forms may appear as swirling, drawn out, or island-like cloud wisps. Also refers to a running or swirling form of HADA.