The Hazama school (Hazama- 間派), also known as the Kameyama makers, emerged in the castle town of Kameyama in Province from around the Genroku era (1688-1704). The school's founders were members of the Kunitomo (国友) family, originally matchlock gunsmiths (teppou kaji) who had lived in Omi Province. As the record, "from the Genna era onward, with the advent of nationwide peace, firearms became unnecessary, and not a few of them turned to making ." Kunitomo Sadaei (国友貞栄), regarded as the representative master of the school, relocated to Kameyama and "attempted to adapt the inlay techniques used on hinawajuu (matchlock firearms) to the making of ." Works bear either the single-character signature "間" (Ma) or personal names such as Kunitomo Sadaei and Masaei (正栄), linking the school's named artisans to a shared workshop tradition rooted in the military metalworking crafts of the Kunitomo lineage.
The Hazama school's defining contribution is sahari-zougan (佐波理象嵌), an inlay technique employing sahari, a distinctive alloy of copper, tin, and lead. As the texts observe, although sahari itself is known from antiquity — "it appears, for example, among the treasures of the Shousouin" — "its use on is not found outside this lineage." The school's style is consistently described as "highly individual" (isshuu dokutoku): inventive variant forms (kawari-gata) including the characteristic goishi-gata (go-stone shape), grounds of iron, plain copper (), and the rarer , and "large-scale bold designs" (oomoyou no ishou) in which the and are "strikingly different." Techniques attested across the corpus include -zougan (applied inlay), takanikubori (high-relief carving) in shakudou, -zougan (flat inlay), and the kusarashi (fired and corroded) surface treatment. A distinctive physical trait of Hazama sahari-zougan is the presence of fine holes where inlay has partially flaked — a feature the regards not as a defect but as one that "heightens the work's elegant charm (gashu)."
The Hazama school occupies a singular position within the broader kinko tradition as the only lineage to have applied sahari inlay to production. The consistently note that Hazama works "have long been prized" for "their superior designs and for the intriguing flavor of their inlay." The school's representative master Kunitomo Sadaei is singled out for pieces that are "the most accomplished and representative" of the group, while unsigned works bearing only the "間" character are valued for compositions that are "bold and brimming with mass" yet shift taste between obverse and reverse — a hallmark the identifies as expressing "the distinctive character of Ma." The school's origin as firearms craftsmen who transferred their metalworking mastery to a peaceful art form, and their creation of a decorative vocabulary without parallel elsewhere in production, secure their place as one of the most distinctive regional schools of the mid- period.