Japan Association of Mineralogical Sciences

摘要

The Higashimatsuura basalt, distributed throughout the Higashimatsuura peninsula, Saga Prefecture, Kyushu, Japan, comprises five lithological units. The units are based on the stage of volcanic activity. The most recent stage has yielded three new minerals: kimuraite-(Y) (Nagashima et al. 1986, American Mineralogist 71: 1028-11033), kozoite-(Nd) (Miyawaki et al. 2000, JMPS 98: 137-141), and kozoite-(La) (Miyawaki et al. 2003, American Mineralogist 85: 1076-1081). The Higashimatsuura basalt is the only basalt reported to include these rare earth minerals. Their regional distribution and detailed mineralogy, except at the type localities, remain to be investigated. My mineral-ogical study of the Higashimatsuura basalt commenced in 2000, and continues now with my students Tomotaka Kusuzaki, Yasuhiro Takai, and Ayaka Shobu, and my colleague Mr. Shoichiro Iwano, an amateur mineralogist who contributed to the discovery of kimuraite and kozoite-(La).