Special Lecture "Minerals of Kyushu"

Kyushu comprises three main geologic units: (1) basement rocks distributed in northern Kyushu, (2) subduction complex in southern Kyushu and (3) late Cenozoic volcanic rocks, which cover widely the former two units. Representative minerals of Kyushu and mineral collections in Kyushu University were briefly reviewed. <BR> 1. Classical mineral locality of Kyushu<BR> Minerals of Kyushu were studied since the first introduction of western mineralogy to Japan after Meiji Restoration. Classical minerals (localities) are summarized on the mode of occurrence as follows. <BR> 1-1. Minerals in contact metasomatic deposit<BR> Scheelite (Sannotake mine, Fukuoka Prefecture). Axinite (Obira mine Oita Prefecture). Scorodite and parasymplesite (Kiura mine, Oita Prefecture, T. Ito et al., 1954). Danburite(Toroku mine, Miyazaki Prefecture). A mineral similar to black scheelite with different chemical composition from Sannotake mine was named "trimontite" by Iwasa (1885). Later analysis showed "trimontite" to be scheelite and the name was discarded.<BR> 1-2. Minerals in pegmatite<BR> Lepidolite (Nagatare, Fukuoka Prefecture). Uraninite and monazite (Kotoge and Masaki, Fukuoka Prefecture). Rock crystal (Shishigawa Miyazaki Prefecture). First mineralogical report of Nagatare pegmatite was made by S. Ko in 1933. Next year the pegmatite was assigned as national monument of "Nagatare Pegmatite Dyke with Lepidolite".<BR> 1-3. Minerals in metamorphic rocks and serpentinite.<BR> Magnetite (Torika, Nagasaki Prefecture). Corundum (Toyofuku, Kumamoto Prefecture). Brucite (Sasaguri Fukuoka Prefecture). Millerite (Wakayama mine, Oita Prefecture). Kammererite and uvarovite (Washidani mine, Oita Prefecture). I. Iwasa (1877) reported two new minerals of "bungonite" and "japanite" on chemical analysis for purplish red and green minerals from Washidani mine, although later investigation revealed that these minerals were kammererite and uvarovite, respectively.<BR>1-4. Minerals in late Cenozoic volcanic rocks.<BR> Augite (Nishigatake, Saga Prefecture). Kimuraite(Hisen, Saga Prefecture, Nagashima et al., 1986). Tridymite (Ishigamiyama, Kumamoto Prefecture). Imogolite (Hitoyoshi, Kumamoto Prefecture, Yoshinaga & Aomine, 1962). Osumilite (Sakkabira, Kagoshima Prefecture, Miyashiro, 1956).<BR> 2. Mineral collections in Kyushu University<BR> The Ko Collection of minerals is one of the most important mineral collections in Japan as containing large crystal samples mainly from Japan. The mineral specimens, amounting to about 1,200 (159 species), are mainly crystal samples occurred from Japan, including from Korea and Taiwan in the period 1890's-1930's when metal mining of Japan was most active. It was collected by the late Sokichi Ko, who was a professor of economic geology at the Department of Mining, Kyushu University from 1911 to 1929. The arrangement of the mineral specimens was primarily made by the late Yohachiro Okamoto and is based on the classification of the Dana's System of Mineralogy, sixth edition (1892). Shirozu et al. (1971) published a comprehensive catalogue of the collection. Other representative collections are Yohachiro Okamoto Collection and Toyofumi Yoshimura Collection in Faculty of Science, mineral and ore collections in Faculty of Engineering. Database of these collections can be found in home page of Kyushu University Museum (http://database.museum.kyushu-u.ac.jp/search/mine/).