Kinju, whose name the published commentary reads as Kaneshige, is counted since antiquity among the Masamune Jittetsu, the ten great disciples of Sōshū Masamune, and stands with Kaneuji at the headwaters of the Mino tradition. The published sources, citing the Kokon Meizukushi, give his Buddhist name as Dōa and his origin as Tsuruga in Echizen Province, recording that 'his Buddhist name was Dōa; a resident of Tsuruga in Echizen, an excellent master craftsman; he crossed over to Seki and resided there'[[c:1]]. Together with Kaneuji he is named the source of the Mino smiths, 'a founder, alongside Kaneuji, of the wellspring of Mino swordsmithing'[[c:2]]. The Kōzan Oshigata preserves two tantō dated to Jōji 2 (1363), which fix his Nanbokuchō activity, and his securely signed pieces do not go back before that period, so the published record treats his direct tie to Masamune as a matter of tradition rather than proof.
His hand is read as Mino-den held apart from the Shizu group, and the distinction the judges draw is precise. Where the Shizu work runs to pointed togari-gunome, Kaneshige tempers a calm line of gunome whose heads are round, set in a linked series: the published sources describe it as a temper 'in which, rather than pointed gunome, rounded-headed gunome run in a linked sequence'[[c:3]], accompanied by ko-nie, the whole 'calmer in overall impression than the Shizu group'[[c:4]]. Over that quieter yakiba he lays a shallow notare or a suguha-toned base mixed with small togariba and, on the mumei katana, kataochi-like gunome; ashi enter, the nioiguchi tends to brightness, and fine kinsuji and sunagashi run through the temper with yubashiri and nie-hotsure gathering along the habuchi. This activity in nie is the Sōshū inheritance carried into Mino steel, and the published commentary names it a key point of appreciation in his work.
The jigane is the constant tell. He forges an itame mixed with mokume and nagare that stands somewhat more than the Shizu jigane and runs toward masame near the edge, the steel laid with thick ji-nie and worked with frequent chikei, and on the long blades a whitish shirake often rises into an utsuri-like aspect. Where the forging tightens it becomes a compact ko-itame, as on the one signed tachi, with fine ji-nie densely set; where it opens it stands a little, the grain showing on the surface. The bōshi answers the temper, running midare-komi to a small round or a yakizume-toned point and swept into hakikake, sometimes with kinsuji entering the turnback. Across both his registers the jigane and its standing grain, more than any single feature of the edge, is what the judges read first.
Two faces divide his record. The first is the research base: a small number of ubu, two-character signed hira-zukuri tantō and wakizashi, wide in body with thin kasane, several elongated in the Enbun-Jōji sun-nobi proportion, and one rediscovered signed tachi, suriage but holding its koshizori, that runs a continuous ko-gunome from base to point. These signed pieces are not uniform in manner: some are a quiet notare, some a linked ko-gunome, and the published sources note that a few run to a hitatsura-like full temper, evidence that the manner of the name is varied. At the base of the tantō he carves a devotional program, gomabashi and a koshi-hi, a raised suken, paired bonji, and on one wakizashi a four-pillar dai-dangu motif read as a symbol of Fudō. The second face is the larger one, the ō-suriage mumei katana and naginata-naoshi judged den Kaneshige, wide and imposing in the Nanbokuchō form, whose attribution rests on era and school where no single decisive tell settles it. Of the rediscovered signed tachi the published sources stress the weight of the find, 'the significance of confirming this work as a signed tachi by Kaneshige is therefore considerable'[[c:5]], for until then his long blades were known only as mumei attributions.
What sets Kaneshige apart within Mino is exactly what the judges name. He is held away from the Shizu group by the quieter, rounder gunome and the more standing grain, the published commentary repeatedly affirming that his work 'differs in character from that of the Shizu group'[[c:6]] while remaining unmistakably Mino-den of the Nanbokuchō. He is the founder beside Kaneuji rather than a follower, the smith whose calmer, nie-laden manner gave the Seki tradition one of its two roots; the workshops of Seki carried that Mino-den hand forward into the Muromachi, when the province became one of the great centers of sword production. The published record also notes a second-generation Kaneshige to whom certain wakizashi are attributed, so the name continues past the founder.
For the collector he is a rare and early Mino name. Fujishiro grades him Jō-jō saku. He has no National Treasures and no Important Cultural Properties; his record runs instead entirely through the Jūyō tier, forty-five blades on official record, the great majority ō-suriage mumei katana judged den Kaneshige and only a handful the precious signed tantō, wakizashi and the single signed tachi that anchor study of the name. His blades are preserved in long-held collections and institutions, the Kyoto National Museum among them, and his provenance reaches the Tokugawa shogunal house: one signed tantō was presented to the shogun's family in 1679 to mark the birth of the heir Tokumatsu, passing through the hatamoto Soga Nakasuke. Because almost nothing of his survives signed and the long blades trade only at the upper Jūyō level, a signed Kaneshige is among the rarer things a collector of Mino-den could hope to encounter, coming to light only seldom and, when it does, standing as a document of how the Mino tradition began.
