This is a Juyo-designated mitokoromono (matching set of kozuka, kogai, and menuki) by Ishiguro Koretsune, a prominent maker from the Ishiguro school. The set features an intricate paulownia and phoenix design, with the kozuka and kogai signed by Koretsune. Crafted in the late Edo period, it showcases high-quality shakudo with nanako ground, takabori, and lavish gold inlay.
Certificate reading — 銘 小柄・笄 銘 石黒是常鐫 / 目貫 割短冊銘 石黒斉・是常
NihontoWatchmei · Ishiguro · Edo
Ishiguro Koretsune
Edo
Signed
Jūyō #28 (NBTHK)
Machibori · Musashi
3 pieces on the market now
Ishiguro Koretsune was the eldest son of the first-generation Masatsune, the founding master of the Ishiguro school within the broader Yokoya lineage. Known by the common name Shukichi, he employed the art names Togakushi and Shuhosai. Together with the second-generation Masatsune, Koretsune served as a substitute maker (daisaku) for his father, assuming a central role in the workshop's prolific output during the late Edo period. He is further credited with having provided technical guidance to the first-generation Koreyoshi, thereby transmitting the school's methods to the next generation. It is recorded that Koretsune died in the prime of life, lending a particular rarity to his surviving oeuvre.
Koretsune's carving methods are characterized by the NBTHK as "dignified and sumptuous, yet steadfast and reliable." Working principally on shakudo nanako-ji grounds, he excelled in bold takabori with polychrome iroe employing gold, silver, shakudo, shibuichi, and hi-irodo (scarlet copper). His command of sculptural depth is especially notable: by subtly lowering the hiraniku from the seppa-dai toward the rim, he achieved a heightened sense of perspective that transforms the tsuba surface into what the examiners describe as "a magnificent and excellent screen-painting transformed into metalwork." His bird-and-flower subjects — from phoenix and paulownia to raptorial birds upon aged plum trees — display vigorous, spreading forms and a courageous bearing that constitute "the very essence of the Ishiguro school."
Koretsune's significance rests both in his role as the vital link between the first-generation Masatsune and the school's later flourishing, and in the exceptional quality of his individual production. The NBTHK has consistently praised works in which "Koretsune's full strengths are amply displayed[[c:1]]," noting in particular his lavish yet controlled use of gold and his ability to render subjects with an immediacy "such that the bird seems about to burst forth from the surface." Because examples by Koretsune are acknowledged to be scarce, each surviving work is valued not only as a demonstration of supreme craftsmanship but also as "important material for the study of the Ishiguro school[[c:2]]."
Where Koretsune 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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Machibori · Edo
19 pieces on the market now
The Ishiguro school was founded by Ishiguro Masatsune, born in Horeki 10 (1760), who trained under Kato Naotsune and Yanagawa Naomasa within the broader Yokoya lineage before establishing an independent atelier that would become one of the most celebrated machibori ("town carving") workshops of the late Edo period. Masatsune combined one character from each teacher's name to form his professional identity, and under the art name Togakushi he attracted a succession of gifted pupils -- Masayoshi, Masaaki, Koretsune (his eldest son), Koreyoshi, Masahide, and Masahiro -- who carried the school's distinctive manner through the final decades of the Tokugawa period and into the Meiji era. Centered in Edo, the Ishiguro lineage operated within the machibori sphere, producing fittings for discerning warrior-class and merchant patrons rather than under the hereditary commissions of the Goto iebori tradition, a commercial independence that fostered pictorial ambition and technical innovation. The collective technical identity of the Ishiguro school is defined by a painterly naturalism executed through takabori upon shakudo nanako-ji grounds, enriched by lavish polychrome iroe employing an unusually wide palette of colored metals -- gold, silver, shibuichi, suaka (scarlet copper), oborogin, and hi-irodo. The school's signature subjects are kacho-zu (flowers and birds), rendered with a naturalistic, sketch-like fidelity grounded in close observation from life. Masatsune established this direction, transforming the Yanagawa manner into a personal idiom centered on birds of prey and bird-and-flower compositions that became the hallmarks of the house. His works are characterized by an "honest, finely detailed manner" and a "clear and limpid spirit" achieved through masterful use of open space. Masayoshi, who succeeded as third head, brought the school's painterly idiom to its fullest expression: front and reverse surfaces are linked through continuous branches and contrasting water motifs, male and female birds are paired with deliberate compositional care, and the interplay of a-un expression lends narrative depth to each scene.
His compositions on iron migaki-ji grounds demonstrate equal command, with kin-sunago zogan evoking atmospheric haze. " Koretsune served as vital link between the founder and the school's later flourishing, with takabori described as "dignified and sumptuous, yet steadfast and reliable," and a command of perspective achieved by subtly modulating surface depth. Koreyoshi, credited with ability "surpassing that of his father" Masayoshi, brought the school's character to its fullest late-period expression, producing work likened to the nishiki-e color woodblock prints of the age. The Ishiguro school's significance within the tosogu canon rests upon its transformation of the Yokoya-Yanagawa classical discipline into a pictorial art of extraordinary chromatic richness and compositional sophistication. Where earlier metalworking traditions relied predominantly on monochrome shakudo or gold tonalities, the Ishiguro masters deployed polychrome iroe with a sumptuousness "that never lapses into vulgarity" -- a balance of brilliance and restraint that defines the school's aesthetic. Masatsune's founding generation retained a martial vigor suited to warrior taste that distinguished his work from the "more purely ornamental output of later Ishiguro artists," while the successive generations of Masayoshi, Masaaki, and Koreyoshi progressively refined the school's decorative vocabulary toward an opulence that mirrored the cultural efflorescence of the Bunka-Bunsei era. Complete soroe-kanagu sets and unified issaku suites represent the school's highest achievement, demonstrating rigorous thematic coherence across every component of a mounting. The NBTHK has consistently praised the school's finest works as pieces in which "the Ishiguro school's distinctive character" is left "nothing unexpressed," and the tradition's enduring legacy is that of a workshop which, across four generations, brought the art of polychrome metalwork to its most accomplished and visually resplendent expression in Edo-period Japan. Learn more →
| Smith | Era | Designated |
|---|---|---|
| Masayoshi政美 | — | 30 |
| Masatsune政常 | — | 17 |
| Masaaki政明 | — | 19 |
| Koretsune是常 | — | 4 |
| Koreyoshi是美 | — | 4 |
A blade of top-grade workmanship and condition, formally judged to rank with a nationally recognized Important Art Object (Jūyō Bijutsuhin). Awarded only at the NBTHK’s competitive annual examination.
Of Japan’s roughly 2.5 million registered swords, only 12,357 (about 1 in 202) have ever attained Jūyō.
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 site3 day inspection period on all sales. Items can be returned for any reason for a full refund, less return shipping cost. Returned items must be in the same condition as when purchased.
$56,000
