The Kamioka mine, Gifu prefecture, working the largest lead and zinc deposit in Japan, lies in the eastern corner of the Hida gneiss complex. The skarn minerals in this mining district are genetically divided into the following three groups. Skarn A : Recrystallized skarn, formed by a regional metamorphism of impure limestone beds. The creation of skarn A is same in age to the formation of the Hida metamorphic complex. Skarn B : Zoned skarn along the contact between limestone and Inishi syenitic rock, having a same origination to Shimonomoto granite. The formation of skarn B is closely related to the intrusion of Shimonomoto granite. Skarn C : Pyrometasomatic skarn, formed by pyrometasomatic replacement of limestone probably after the deposition of the Mesozoic Tetori formation. The ore deposits of the Kamioka mine are composed of the pyrometasomatic skarn (skarn C) called "Mokuji" and the hydrothermal deposits called "Shiroji". Skarn A and skarn B have no genetical relation to the ore deposits. But skarn A acts the valuable role for the stratigrahical classification of ore deposits and limestone beds.

Original Papers