Reizei Sadamori (冷泉貞盛) was a swordsmith of Chikuzen Province active during the Nanbokucho period, belonging to the Kongobyoe (金剛兵衛) lineage -- one of two principal groups working in Chikuzen alongside the Samonji school. Among his surviving works, a tanto inscribed "Chikushu Reizei Sadamori, Shohei 25, first month" (designated Important Art Object) serves as what the NBTHK consistently terms "a precious standard when appraising and confirming works as being by Reizei Sadamori." Signed examples are extremely few, rendering each authenticated piece of considerable documentary value for the study of this smith's workmanship.

The defining technical characteristic of Sadamori is a "Yamato temperament" discernible in both jihada and hamon -- a phrase the NBTHK repeats with striking consistency across every assessment. The jigane shows a steel color (kanairo) described as "slightly clouded and blackish," with chikei "frequently interwoven" throughout the surface. His hamon is characteristically a narrow hoso-suguha with a nioiguchi that "tends toward a tightened feeling," accompanied by ko-nie and activity along the habuchi in the form of hotsure, uchi-noke, and nijuba. The forging is typically itame-hada with a tendency toward flowing and standing grain, often mixed with mokume and inclining toward masame -- particularly near the cutting edge. Despite the restrained width of the temper, Sadamori's blades yield abundant visual interest: sunagashi and kinsuji appear from base to tip, and in his broader-tempered works, notare mixed with gunome produces a richly varied hamon of "richly flavored workmanship."

The NBTHK consistently characterizes Sadamori's blades as possessing "a subdued, austere taste" that "strongly exhibits the coloration characteristic of Kyushu works." His finest pieces are praised for the way in which "although it tempers a narrow suguha in a well-forged steel possessing a supple quality, abundant activity can be discerned along the boundary of the hardened edge, producing a blade of deep flavor." The commanding taihai of his long blades is noted as dignified and robust, and the condition of both ji and ha is frequently described as kenzen -- sound and well-preserved. Within the Kongobyoe tradition, Sadamori occupies a distinctive position: a smith whose quiet austerity and Yamato-inflected steel yield blades of contemplative depth, set apart from the more flamboyant Soshu-influenced work of his Samonji contemporaries.