An o-dachi bearing the vermilion shu-mei 千代鶴国安 is preserved at Atsuta Jingu, the kind of dedicated great-sword in which the name of this smith survives most directly, for almost everything else on his designated record is a katana greatly shortened and left unsigned, handed down with the den attribution to Rai Kuniyasu. The published sources transmit Kuniyasu as a man born in Yamashiro Province and, by one tradition, a grandson of Rai Kunisue, who later "moved to Echizen and became the founder of the Chiyozuru lineage"[[c:1]]; the reference works place him around the Joji and Sadaji years of the Nanbokucho period, noting that "the sword reference works set his era around the Joji era"[[c:2]]. His is a hand read as the Rai tradition carried out of the Yamashiro capital and inflected by the province that received it, and at first glance a blade of his "can appear akin to works of the Yamashiro Rai homeland, particularly those around Rai Kunimitsu"[[c:3]], yielding only slightly on close examination, so that, as the published record puts it, the received tradition "is judged acceptable"[[c:4]].

The feature that marks him apart from that homeland is the jigane. Where the Yamashiro Rai smiths forge a tight, refined itame, Kuniyasu's itame is mixed with mokume and, in places, nagare-hada, and it stands somewhat open, a hada-dachi tendency the published sources read as his provincial flavor. Over this standing jigane the ji-nie forms thickly, at times dust-fine, and the chikei enter frequently, while the steel takes a slightly blackish tone and a whitish cast, the shirake-gokoro that recurs across his blades. The published commentary makes this the decisive point of appraisal: it is precisely because the grain stands and the steel turns whitish and dark that "here the appraisal to Rai Kuniyasu is confirmed"[[c:5]], the work judged not the homeland's but his.

The temper is a chu-suguha into which small ko-gunome mix, the base sometimes carrying an extremely shallow notare tendency. Along the habuchi the edge is restless beyond what the homeland shows: hotsure, kuichigai-ba and at times nijuba appear, ashi and yo enter, thick nie adheres and in places flares into a coarser, especially brilliant nie, while fine kinsuji and sunagashi run through a bright nioiguchi. The boshi ranges from a quiet ko-maru with hakikake to a far more active turnback, on one blade the nie growing strong and breaking up along the omote and running to vigorous hakikake on the ura with a flame-like, kaen impression. Of one Nanbokucho katana the published sources write that these features "clearly express the characteristics of Rai work of the Nanbokucho period"[[c:6]], the Rai inheritance still legible beneath the provincial cast.

Within this one prime manner the blades fan out along a single axis, from the restrained to the flamboyant. At the quiet end stand pieces whose chu-suguha runs nearly straight, the activity confined to slight hotsure and a kuichigai-ba nuance along the edge. At the active end stands the Joji-era katana of the 61st Juyo session, dated by the reference works to around the Sadaji era, in which "an especially brilliant, coarser nie"[[c:7]] sparkles here and there within the bright ha and the boshi turns to its flame-like form; of this blade the published sources observe that "a rusticity exceeding even the Yamashiro homeland is conspicuous even in the boshi"[[c:8]], naming the very excess of activity as the mark of the provincial workshop. The surviving blades are o-suriage and mumei almost without exception, so that the recognition rests on this reading of ji and ha rather than on a signature, the lone exception being the dedicated shu-mei o-dachi.

The published sources set Kuniyasu in relation to his school by resemblance and slight distinction rather than by contrast. Upstream he stands within the Yamashiro Rai line, near enough to Rai Kunimitsu that a first impression can mistake the two; the gap is one of refinement, the homeland's ji and ha holding a degree of polish his yield. Downstream he is the founder, the smith from whom the Chiyozuru workshop of Echizen descends, and the very features that distinguish his blades from the capital, the standing grain, the blackish whitish-cast steel, the rustic edge and boshi, are the provincial inflection that opens that local tradition. The bright midare activity and the brilliant coarse nie of his most active work set him apart on his own grounded terms, a Rai hand turned rustic in the north.

Fujishiro records no rating for him and his designated output is modest: five works carried to Juyo, with no National Treasure, no Important Cultural Property and no Tokubetsu Juyo among them, four of the five the o-suriage mumei katana that carry the Kuniyasu attribution and one the signed Mino piece that belongs to a different hand. No early daimyo provenance is recorded for his blades. What survives in a public sanctuary is the shu-mei o-dachi held at Atsuta Jingu, a great-sword preserved as patrimony rather than as a thing that trades, and it is in that dedicated piece, not in the market, that his name is read most plainly. None of his designated work is locked away as inalienable cultural property, so the handful of Juyo katana sit in the tradeable tiers; even so, a blade securely appraised to the founder of the Chiyozuru line is encountered only rarely, and the collector who meets one meets a Rai inheritance read through the steel of Echizen.

An o-dachi bearing the vermilion shu-mei 千代鶴国安 is preserved at Atsuta Jingu, the kind of dedicated great-sword in which the name of this smith survives most directly, for almost everything else on his designated record is a katana greatly shortened and left unsigned, handed down with the den attribution to Rai Kuniyasu. The published sources transmit Kuniyasu as a man born in Yamashiro Province and, by one tradition, a grandson of Rai Kunisue, who later "moved to Echizen and became the founder of the Chiyozuru lineage"[[c:1]]; the reference works place him around the Joji and Sadaji years of the Nanbokucho period, noting that "the sword reference works set his era around the Joji era"[[c:2]]. His is a hand read as the Rai tradition carried out of the Yamashiro capital and inflected by the province that received it, and at first glance a blade of his "can appear akin to works of the Yamashiro Rai homeland, particularly those around Rai Kunimitsu"[[c:3]], yielding only slightly on close examination, so that, as the published record puts it, the received tradition "is judged acceptable"[[c:4]].

The feature that marks him apart from that homeland is the jigane. Where the Yamashiro Rai smiths forge a tight, refined itame, Kuniyasu's itame is mixed with mokume and, in places, nagare-hada, and it stands somewhat open, a hada-dachi tendency the published sources read as his provincial flavor. Over this standing jigane the ji-nie forms thickly, at times dust-fine, and the chikei enter frequently, while the steel takes a slightly blackish tone and a whitish cast, the shirake-gokoro that recurs across his blades. The published commentary makes this the decisive point of appraisal: it is precisely because the grain stands and the steel turns whitish and dark that "here the appraisal to Rai Kuniyasu is confirmed"[[c:5]], the work judged not the homeland's but his.

The temper is a chu-suguha into which small ko-gunome mix, the base sometimes carrying an extremely shallow notare tendency. Along the habuchi the edge is restless beyond what the homeland shows: hotsure, kuichigai-ba and at times nijuba appear, ashi and yo enter, thick nie adheres and in places flares into a coarser, especially brilliant nie, while fine kinsuji and sunagashi run through a bright nioiguchi. The boshi ranges from a quiet ko-maru with hakikake to a far more active turnback, on one blade the nie growing strong and breaking up along the omote and running to vigorous hakikake on the ura with a flame-like, kaen impression. Of one Nanbokucho katana the published sources write that these features "clearly express the characteristics of Rai work of the Nanbokucho period"[[c:6]], the Rai inheritance still legible beneath the provincial cast.

Within this one prime manner the blades fan out along a single axis, from the restrained to the flamboyant. At the quiet end stand pieces whose chu-suguha runs nearly straight, the activity confined to slight hotsure and a kuichigai-ba nuance along the edge. At the active end stands the Joji-era katana of the 61st Juyo session, dated by the reference works to around the Sadaji era, in which "an especially brilliant, coarser nie"[[c:7]] sparkles here and there within the bright ha and the boshi turns to its flame-like form; of this blade the published sources observe that "a rusticity exceeding even the Yamashiro homeland is conspicuous even in the boshi"[[c:8]], naming the very excess of activity as the mark of the provincial workshop. The surviving blades are o-suriage and mumei almost without exception, so that the recognition rests on this reading of ji and ha rather than on a signature, the lone exception being the dedicated shu-mei o-dachi.

The published sources set Kuniyasu in relation to his school by resemblance and slight distinction rather than by contrast. Upstream he stands within the Yamashiro Rai line, near enough to Rai Kunimitsu that a first impression can mistake the two; the gap is one of refinement, the homeland's ji and ha holding a degree of polish his yield. Downstream he is the founder, the smith from whom the Chiyozuru workshop of Echizen descends, and the very features that distinguish his blades from the capital, the standing grain, the blackish whitish-cast steel, the rustic edge and boshi, are the provincial inflection that opens that local tradition. The bright midare activity and the brilliant coarse nie of his most active work set him apart on his own grounded terms, a Rai hand turned rustic in the north.

Fujishiro records no rating for him and his designated output is modest: five works carried to Juyo, with no National Treasure, no Important Cultural Property and no Tokubetsu Juyo among them, four of the five the o-suriage mumei katana that carry the Kuniyasu attribution and one the signed Mino piece that belongs to a different hand. No early daimyo provenance is recorded for his blades. What survives in a public sanctuary is the shu-mei o-dachi held at Atsuta Jingu, a great-sword preserved as patrimony rather than as a thing that trades, and it is in that dedicated piece, not in the market, that his name is read most plainly. None of his designated work is locked away as inalienable cultural property, so the handful of Juyo katana sit in the tradeable tiers; even so, a blade securely appraised to the founder of the Chiyozuru line is encountered only rarely, and the collector who meets one meets a Rai inheritance read through the steel of Echizen.