R1: Characterization and description of minerals (Joint Session with The Gemmological Society of Japan)

[R1P-10] Mineralogy of garnet from Mt. Kutsuna, Matsuyama, Ehime Prefecture

*Shota Oshima¹, Yohei Shirose² (1. Ehime Kensetsu Consultants Co.,Ltd, 2. Grad. Sch., Ehime Univ)

Keywords:garnet, Mt. Kutsuna, almandine, spessartine, garnet-biotite geothermometer

Garnet from the west coast of Mt. Kutsuna, Kitayoshida-cho, Matsuyama, Ehime Prefecture shows various properties such as color, grain-size, and shape. We describe the geology of Mt. Kutsuna and mineralogical properties of the garnet. The mineral species of garnet were almandine and spessartine bearing minor Mg, and Ca. Core-rim textures with inclusion were also observed. The metamorphic temperatures of the hornfels were estimated at 510 to 620 ℃ by garnet-biotite geothermometry.