NihontoWatchConsigned Shinshinto Tanto made by Korekazu in the 5th year of the Ka-Ei era (1851). He is also known as the seventh-gen Ishido Korekazu(七代石堂是一) Mounted in Aikuchi Koshirae and also has Shirasaya Nagasa is 23 cm The first-gen Korekazu was originally from Omi Koku(Today’s Shiga prefecture). It is said that he was a descendant of Ichimonji Sukemune(一文字助宗) from Bizen Koku(Today’s Okayama prefecture). He moved to Edo and founded Edo Ishido school at the beginning of the Edo period. This school flourished during the whole Edo period and became one of the most popular ones in Edo city, Musashi Koku. Ishido Korekazu became an Okakaekaji for the Edo government in 1721, exclusively forging swords for the Tokugawa clan. In total, the smith name “Korekazu” lasted 8th generations. The seventh-gen Korekazu, who was active at the end of the Edo period, is especially highly regarded among Japanese sword experts because of his superb craftsmanship. The 7th-gen Korekazu is also known as Unjyu Korekazu. The seventh gen Korekazu’s real name is Masataro, and he was born in 1820 and learned the sword-forging technique from his uncle Kato Cho Unsai Tsuna Toshi, who lived in Dewano Kuni(Today’s Yamagata prefecture). Later he became a son-in-law of 6th-gen Ishido Korekazu and eventually took over Edo Ishido school. Seventh-gen Korekazu forged swords up until the early Meiji period. He died at the age of 75 in the 24th year of the Meiji era. The 7th-gen Korekazu was ordered to forge a sword for Ise Shrine in Mie prefecture and Toshogu Shrine in Tochigi prefecture. And he was allowed to inscribe the Tokugawa family emblem on these swords. Furthermore, in 1854, he was ordered to forge a sword for sending to the USA and created Naginata for the UK, which was gifts from Japan for diplomatic relations. This fact indicates that Korekazu was one of the Edo government’s trusted swordsmiths and played an essential role at the end of the Edo period. The 7th-gen Korekazu was a great master as well because he trained quite a few renowned swordsmiths, such as Katsumura Norikatsu. His sword style is called Bizen-Den, and he was great at forging blades with Choji Midare Hamon,
Certificate reading — 銘 是 一作 嘉永五年八月（以下切）
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Edo Ishidō (Korekazu line, 7th generation) · Musashi · around 1817-1891
Fujishiro Jo saku · Tōken Taikan top 37%
8 pieces on the market now
A katana dated Bunkyū 2 (1862), made in his forty-fifth year, is singled out by the published sources as an especially outstanding blade in the Bizen manner he favoured, the clarity of both ji and ha splendid. Its maker, Ishidō Unju Korekazu, was born in Yonezawa in Dewa and known by the common name Masatarō. He was a nephew of the Yonezawa domain smith Katō Chōunsai Tsunatoshi and first learned forging under him. He then became the son-in-law of the sixth Ishidō Korekazu and succeeded as the seventh head of the Edo Ishidō house, dying in Meiji 24 (1891) at the age of seventy-five. His working life ran from the closing years of Tenpō into early Meiji, and comparatively many of his works survive. The published commentary counts him among the leading masters of the Shinshintō period, standing shoulder to shoulder in skill with Jirōtarō Naokatsu and Hosokawa Masayoshi.
The published sources describe his hand through a method rather than a motif, and they state it in nearly the same words entry after entry. His work divides broadly into two modes, Bizen-den and Sōshū-den, but his true forte was the Bizen chōji that may be called the hereditary specialty of the Ishidō house. Whereas many Shinshintō smiths working in the Bizen manner tempered their chōji in nioi-deki, Korekazu tempered his in nie-deki, and the commentary concludes that "in this one can discern his originality"[[c:1]]. Two entries put the reputation in a phrase: he is the smith described as having "tempered Bizen-style chōji-midare in nie"[[c:2]]. One entry also gives the development behind it. His early works, like those of his teacher Tsunatoshi, show a tight nioiguchi and a chōji-midare with ashi; in later years he tempered this chōji in small nie, which the source says brought a further degree of variation into the ha[[c:3]].
On the typical blade the chōji is mixed with gunome, ko-chōji, ko-gunome and slightly pointed elements. The ashi enter long and frequently, the nioi is deep, and the nie lies thick, with patches of coarser nie that leave the temper a little uneven. Sunagashi runs through the ha on about three of every four of his blades, often joined by kinsuji and nie-suji, and the nioiguchi is bright and clear. The jigane is a tightly forged ko-itame, at times mixed with mokume or flowing grain. Its ji-nie lies in a fine, thick cover with fine chikei entering frequently, and where it packs hardest it approaches a muji-fū surface. One entry singles out this forging as especially strong even within his own work[[c:4]]. The bōshi runs midare-komi to a ko-maru, often with hakikake, and one entry finds in its handling the mannerisms of Tsunatoshi, from which it infers a stylistic tie between the two smiths. The blades are robust ubu katana, wide in body with thick kasane, the point a long chū-kissaki or an ō-kissaki, the tang finished with ō-sujikai file marks and a long signature.
Beside this Bizen core the published sources record other registers. Korekazu, one entry notes, himself claimed a proficiency in Sōshū-den[[c:5]], though most of his finest works are Bizen. A daishō of Ansei 2 (1855) succeeds in the Sōshū manner and comes with a formal rō-nuri kamishimo-zashi mounting whose full set of fittings is by Yokoya Sōju. A gassaku katana with the Aizu smith Kakuda-suke Gengō, his exact contemporary, records that Gengō forged the blade and Korekazu applied the temper; the judges found that it seems "entirely the work of Korekazu"[[c:6]]. The rarest face is suguha. A long, robust katana of Ansei 5 (1858) over a muji-fū forging carries a suguha-based temper with gunome, deep in nioi with a bright nioiguchi, and the source calls it "a comparatively gentle style" for him[[c:7]].
The record keeps returning to the same blades as his measure. Of one Juyo katana, whose ko-itame carries dust-fine thick ji-nie and whose temper shows kinsuji and nie-suji with unusual vigour, the commentary writes that it is "a blade in which the true specialty of Korekazu is brought forth without reservation, demonstrating an exceptionally distinguished workmanship"[[c:8]]. Other long blades with ō-kissaki are praised for holding together without strain despite their length. His work also carries the marks of its moment. One katana is carved with the characters printed in the source as 「譲夷」, a carving the entry reads as showing the temper of the age. Another was made for Sanada Kōkan, a retainer of the Sendai Date house, and its tang carries a verse in man'yōgana: 「この太刀に貯めし心は身一つよ, 守るたまかは我が君のため」 ("the heart I have stored in this tachi is but one: to protect, indeed, for my lord").
Fujishiro grades him Jō saku, and the Tōkō Taikan values him at four hundred. He has no National Treasure and no Important Cultural Property. Twenty-four of his katana are designated Juyo, at sessions from 1964 to 2022, and a twenty-fifth, a katana dated Kaei 6 (1853), is recorded in Honma's inventory of the Imperial collection. That entry adds a note of regret: his was the era of the Meiji sword ban, and "it is regrettable that he could not fully exercise his skill"[[c:9]]. All of these blades are signed, and most are dated. Because comparatively many survive, a signed, dated Korekazu katana comes to market from time to time rather than once in a generation, and a sound example in his nie-deki chōji is among the more attainable ways to hold the late Bizen revival at its most personal.
Where Korekazu stands among comparable artisans: across all of nihontō, and within tradition, era, and period. The tiers (Foremost · Leading · Major · Notable) weigh official designations from the NBTHK and Japan's Agency for Cultural Affairs, together with historical honors of lasting repute such as the Sansaku and Meibutsu-chō.
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Years he was demonstrably active, proven by signed-and-dated blades
Shinto · Musashi
17 pieces on the market now
The Edo Ishido school (江戸石堂) is the capital branch of the Ishido lineage, a body of shinto-era smiths who carried the Bizen choji tradition into Edo and there pursued a single deliberate project: the revival, in the brighter steel of the early-Edo forges, of the flamboyant choji-midare worked by the medieval Fukuoka-Ichimonji masters of Bizen. The school's makers came up from Omi by way of Kyoto rather than directly, the Akasaka-signed blades of Mitsuhira fixing that route, and several of its leading hands trace to the Kyo-Ishido line before the move to the capital; Heki Mitsuhira, eldest son of Yamashiro-no-kami Ippo, and Tsushima-no-kami Tsunemitsu stand as the twin pillars of the early school, while the Edo Ishido Korekazu line carried the house specialty forward, the seventh-generation Korekazu keeping it alive through the nineteenth-century shinshinto revival. A separate Edo strand runs through Yamato-no-kami Yasusada, whom recent research and the Shinto Bengi place within the Kishu Ishido group, a Kanbun-era master of the capital whose temper turns toward the angular rather than the choji of his school-fellows. What binds the school is a shared vocabulary rather than a single hand. The defining work is the choji-midare tempered over a bright shinto ko-itame, a crowded line mixing gunome, ko-gunome, round-topped choji and small choji with angular and pointed elements, the yakiba rising and falling in marked height, the ashi and yo entering vigorously, the nioiguchi clear; on the most successful pieces a midare-utsuri stands in the jigane, the koto-Bizen reflection raised again on a shinto blade, the single feature that carries the Ichimonji comparison furthest. Mitsuhira tempers this revival chiefly in nioi, and the NBTHK reads his choji over its utsuri as the fullest realization of the school's program, a splendid choji-midare that recalls the old Ichimonji. Korekazu departs precisely here: where the other Bizen-leaning smiths held their choji in nioi-deki, he forged the house pattern in nie-deki, deep in nioi and thick in nie over a ko-itame approaching a muji-fu tightness, with sunagashi, kinsuji and nie-suji threading the edge, a Bizen pattern carried on a Soshu-leaning base.
Yasusada marks the school's outer divergence, working a notare mixed with gunome that boxes at peak and valley, the nioiguchi inclining to a subdued shizumi and a steeply raised iori-mune among his marks, his Soshu-leaning nie temper inherited through Kaneshige. Across all of them the jigane is the constant that underwrites the edge, a densely forged ko-itame, sometimes mixed with mokume, the ji-nie laid dust-fine and chikei entering well. To kantei an Edo Ishido blade is to read a revived Bizen choji set on an unmistakably shinto ji: the choji-midare draws the eye to old Ichimonji, but the steel beneath is the bright, clean forging of the Kanbun and later forges, frequently on the broad body, thick kasane and contracted chu-kissaki of the era, with Mitsuhira's transitional silhouette retaining a touch of funbari and standing sori. The utsuri when present confirms the school's intent; the choice of nie-deki over nioi-deki separates Korekazu from his fellows; the boxed notare and shizumi nioiguchi mark out Yasusada, whose hand is read against Kotetsu rather than against his school. The NBTHK ranks the best of these makers among the leading smiths of their respective ages, Mitsuhira as one of the most skilled to represent the Edo Ishido and Korekazu beside Jirotaro Naokatsu and Hosokawa Masayoshi among the late-Edo masters. Provenance is generally quiet, held in private and public hands rather than great houses, though the school's blades carry the texture of their moment: the Yamano gold-inlaid cutting-test inscriptions recur on Yasusada and on Mitsuhira's earliest dated work, one Korekazu blade is recorded in Honma's inventory of the Imperial collection, and his man'yogana and joi-slogan inscriptions voice the late-Edo current that the school's final flowering of Bizen-den outlived. Learn more →
| Smith | Era | Designated |
|---|---|---|
| Korekazu是一 | 1817-1891 | 25 |
| Yasusada安定 | 1618-1685 | 20 |
| Mitsuhira光平 | 1619-1685 | 10 |
| Yasusada安定 | 1673-1681 | 0 |
The Shinshintō revival
Around 1800 Suishinshi Masahide argued in his writings that the craft must return to the old masters’ methods: the fukkotō revival. His greatest successor Naotane worked convincingly in Bizen and Sōshū manners that had been dead for centuries.
Certifies a genuine blade worth preserving: a signature confirmed correct, or, if unsigned, an era, province, and school that the NBTHK can reliably identify.
The NBTHK (Nihon Bijutsu Tōken Hozon Kyōkai, the Society for the Preservation of Japanese Art Swords) is a public-interest incorporated foundation founded in 1948 and supervised by Japan’s Agency for Cultural Affairs (Bunkachō); it is based at the Japanese Sword Museum in Tokyo. Its expert panels physically examine each submitted work (shinsa) and issue a certificate (kanteishō) ranking it by artistic and historical merit. NBTHK papers are the most widely recognized standard of authentication for Japanese swords and fittings.
NBTHK official siteA$4,500