In Ezuri mine, Mn-minerals such as braunite, serandite, Mn-dioxide and Mn-carbonate were found abundantly at the hematite-quartz zone just on or the same horizon as that of Ezuri black ore deposits. The part containing braunite, serandite and others cuts sharply the part of colloidal Mn-dioxide. Therefore, it seems that some raise of temperature and pressure caused recrystallization of braunite, serandite and others from Mn-dioxide.
Stilbite also was found only in the cracks of porphyritic dacite (lava flow or shallow intrusion) that lies above the ore deposits.
