Chalcopyrite blebs and lamellae intergrown with sphalerite, which are similar to those in natural ores, were experimentally formed at the condition of the temperature =400°C and the PH₂O=400 kgf/cm² by reacting Fe-rich sphalerite with Cu-bearing aqueous solutions. This fact verifies a hypothesis that chalcopyrite inclusions in Fe-bearing sphalerite are replacement product. Analytical results by electron microprobe analyses for the reacted sphalerite intergrown with chalcopyrite have proved that replacement mechanisms are not so simple and that copper substitutes not only zinc but also iron in sphalerite at an advanced stage of replacement.

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The geologic unit comprising the Jurassic accretionary complex in the Kaminokuni area in the Southwestern Hokkaido is newly defined as the Kaminokuni Terrane. It is composed of the Matsumae Group which is characterized by overlying and underlying tectonic units forming the two-storied structure. The Matsumae Group of the overlying unit (unit 2) consists of the a, b and c formations in ascending order, while the underlying unit (unit 1) is composed mainly of the b formation. These three formations are tectonically repeated within both units.
The a formation is composed of the oceanic greenstone and bedded chert of Late Carboniferous through Permian age and the lower part of bedded chert includes bedded manganiferous iron oxide and manganese ore deposits, in ascending order. The nature and age of formation of these deposits are camparable to those of the Outer Zone of Southwest Japan but are dissimilar to those of the Inner Zone. The b formation consists of Middle to early Late Jurassic mudstone including olistoliths of Permian greenstone, bedded chert reworked from the a formation, and Triassic to Early Jurassic bedded cherts derived from the strata of the neighboring Kamiiso or Toi-Esan Terrane. The c formation is composed mainly of early Late Jurassic sandstone of which the provenance is regarded to be the continent or island arc.
The two-storied structure of the Kaminokuni Terrane was formed during the underplating through the duplex accretion to the South Kitakami massif in post Late Jurassic time.

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K-Ar ages were determined on eight specimens from five W-Mo deposits in South Korea. Muscovites purified from tungsten ore and pegmatitic quartz vein of the Ssangjeon W deposits give ages of Proterozoic. Although biotite in pegmatitic quartz vein of the Ogbang W mine yields much younger age, the occurrences of the deposits in both mines are so similar that the Ogbang deposits seem to have been formed at almost the same time as the Ssangjeon deposits. Muscovites from the Garisan W-Mo and Jangsu Mo deposits give ages of about 170 Ma, and confirm wide distribution of W-Mo mineralization at early Jurassic time. The results for sericites from the Cheongyang W deposits are around 80 Ma, and are almost same as those of the Daehwa W-Mo and Sangdong W-Mo-Bi deposits. In South Korea, W-Mo mineralization is prior to Au-Ag mineralization in Jurassic time, whereas vice versa in Cretaceous time. At the northeastern end of the Ryeongnam massif, tin (-1800 Ma), tungsten (-1500 Ma) and gold (-1100 Ma) mineralizations are overlapped in Proterozoic time.

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The Dome Rock deposit, South Australia is a submarine exhalative copper-cobalt deposit of Early Pro-terozoic age in multiply defomed and metamorphosed metasediments and metavolcanics. Although there is no distinct alteration zone, tourmaline and ferromagnesian silicates are present in the footwall, ore zone and hanging wall. On the basis of optical and chemical studies, tourmaline and ferromagnesian silicates vary from Mg>Fe species in the footwall pelitic metasediments and ore zone to Fe>Mg species in the hanging wall pelitic metasediments, iron formation and albite rocks. This variation is similar to the variation in the Mg and Fe content of chlorites associated with Kuroko deposits.
Tourmaline in the metasediments formed by metamorphism of boron-rich clays derived from hydrothermal fluid-sediment interaction, whereas tourmaline in the sulfide rocks and overlying albite rocks derived from the primary precipitation of boron-rich species such as a boron-rich clay, reedmergnerite or tourmaline from the ore fluid.

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