Go is the name by which Yoshihiro of Matsukura-gō in Etchū is known, and the published sources place him among the ten disciples of Masamune[[c:1]], one of the supreme names in the whole study of the sword. Like Sadamune he left no genuine signed work; every blade that carries his name is ō-suriage and mumei, an attribution resting on the judgment of the Hon'ami and the later appraisers, so the smith survives only through his manner and through the great houses that kept him. He stands at the very end of the Kamakura period and the opening of the Nanbokuchō, when the Sōshū tradition that Masamune had brought to completion was carried west into Etchū.

The jigane is the first thing the published sources reach for. It is an itame, often mixed with mokume and with a flowing nagare-hada that stands up a little, and in places it inclines strongly to masame; over it the ji-nie lies microscopically fine and thick, and chikei enter frequently, so the steel reads bright and clear. The appraisers make a point of the masame-gokoro worked into the hada (柾ごころ), one of the tells they list for his hand, and they single out that the ji and ha together come up a degree brighter and clearer than his fellows[[c:2]].

The hamon is built on a notare, broad and gentle, with ko-notare and gunome mixed in and the temper height tending to broaden from the base toward the monouchi. Ashi and yō enter, the nioiguchi is deep, and the nie lies thick and even, breaking in places into nie-kuzure with standing nie-suji; through the ha run abundant kinsuji and sunagashi, with occasional yubashiri spilling into the ji. Set beside Masamune and Norishige, the published sources call his chikei and kinsuji the calmer (穏やか), yet they note the nie-ashi working busily within the ha and the whole coming up brighter, which is exactly where they locate him.

The bōshi is where Go is most distinctly himself, and it is the feature the published record names outright as a major characteristic of his hand: the point is tempered deep, sweeping with hakikake (掃きかけ) and breaking into a nie-kuzure so that it becomes an ichimai-style bōshi, the whole tip hardened nearly solid. A representative Tokubetsu-Jūyō katana records it precisely, the bōshi burned deep into a single sheet, collapsing in nie and brushing out in hakikake[[c:4]]. Where it does turn back it settles into a quiet ko-maru, the return sometimes running long; but the deep, swept, single-sheet point is the signature, and a profile that gives him only a calm ko-maru has misread the smith.

For the collector the recognition runs in this order: a clear itame with thick fine ji-nie and frequent chikei, masame creeping into the hada, a deep-nie notare carrying kinsuji and sunagashi, and the deep ichimai-swept bōshi above it[[c:3]], the entire ji and ha lit a degree brighter than the surrounding masters. That brightness and clarity is the discriminator the appraisers use to part him from Masamune himself and from Norishige, whose hada stands up more and whose matsukawa is the heavier. Fujishiro places him at Sai-jō saku, the highest rank, and among all Sōshū hands his is reckoned at the summit.

Because nothing of his is signed and so little survives, Go is among the least attainable of all names. Of the work on record a few sit as National Treasures and Important Cultural Properties that can never trade, and the named meibutsu carry the histories of the great daimyō: the Ōkubo Gō (大久保江), which bears a Hon'ami gold-inlay attribution and descended to the Ōkubo of Odawara, and the Kabutokiri Gō (兜切り江), once of the Mizuno family. Others pass through the Uwajima Date family, one of them bestowed by Tokugawa Hidetada on the first lord of Uwajima and kept thereafter as a house treasure, while further blades descended through the Maeda. To meet a Gō at all is to meet a blade the appraisers judged worthy of the very first names, held for centuries by the houses that could command it.

Go is the name by which Yoshihiro of Matsukura-gō in Etchū is known, and the published sources place him among the ten disciples of Masamune[[c:1]], one of the supreme names in the whole study of the sword. Like Sadamune he left no genuine signed work; every blade that carries his name is ō-suriage and mumei, an attribution resting on the judgment of the Hon'ami and the later appraisers, so the smith survives only through his manner and through the great houses that kept him. He stands at the very end of the Kamakura period and the opening of the Nanbokuchō, when the Sōshū tradition that Masamune had brought to completion was carried west into Etchū.

The jigane is the first thing the published sources reach for. It is an itame, often mixed with mokume and with a flowing nagare-hada that stands up a little, and in places it inclines strongly to masame; over it the ji-nie lies microscopically fine and thick, and chikei enter frequently, so the steel reads bright and clear. The appraisers make a point of the masame-gokoro worked into the hada (柾ごころ), one of the tells they list for his hand, and they single out that the ji and ha together come up a degree brighter and clearer than his fellows[[c:2]].

The hamon is built on a notare, broad and gentle, with ko-notare and gunome mixed in and the temper height tending to broaden from the base toward the monouchi. Ashi and yō enter, the nioiguchi is deep, and the nie lies thick and even, breaking in places into nie-kuzure with standing nie-suji; through the ha run abundant kinsuji and sunagashi, with occasional yubashiri spilling into the ji. Set beside Masamune and Norishige, the published sources call his chikei and kinsuji the calmer (穏やか), yet they note the nie-ashi working busily within the ha and the whole coming up brighter, which is exactly where they locate him.

The bōshi is where Go is most distinctly himself, and it is the feature the published record names outright as a major characteristic of his hand: the point is tempered deep, sweeping with hakikake (掃きかけ) and breaking into a nie-kuzure so that it becomes an ichimai-style bōshi, the whole tip hardened nearly solid. A representative Tokubetsu-Jūyō katana records it precisely, the bōshi burned deep into a single sheet, collapsing in nie and brushing out in hakikake[[c:4]]. Where it does turn back it settles into a quiet ko-maru, the return sometimes running long; but the deep, swept, single-sheet point is the signature, and a profile that gives him only a calm ko-maru has misread the smith.

For the collector the recognition runs in this order: a clear itame with thick fine ji-nie and frequent chikei, masame creeping into the hada, a deep-nie notare carrying kinsuji and sunagashi, and the deep ichimai-swept bōshi above it[[c:3]], the entire ji and ha lit a degree brighter than the surrounding masters. That brightness and clarity is the discriminator the appraisers use to part him from Masamune himself and from Norishige, whose hada stands up more and whose matsukawa is the heavier. Fujishiro places him at Sai-jō saku, the highest rank, and among all Sōshū hands his is reckoned at the summit.

Because nothing of his is signed and so little survives, Go is among the least attainable of all names. Of the work on record a few sit as National Treasures and Important Cultural Properties that can never trade, and the named meibutsu carry the histories of the great daimyō: the Ōkubo Gō (大久保江), which bears a Hon'ami gold-inlay attribution and descended to the Ōkubo of Odawara, and the Kabutokiri Gō (兜切り江), once of the Mizuno family. Others pass through the Uwajima Date family, one of them bestowed by Tokugawa Hidetada on the first lord of Uwajima and kept thereafter as a house treasure, while further blades descended through the Maeda. To meet a Gō at all is to meet a blade the appraisers judged worthy of the very first names, held for centuries by the houses that could command it.