R1: Characterization and description of minerals

[R1P-02] Magnetic properties and microstructures of magnetite from Yanahara mine, Okayama, Japan

*Makio Ohkawa¹, Geraldo Magela da Costa² (1. Hiroshima Uni. Sci., 2. UFOP)

Keywords:magnetite, coercivity, Si-substitution, intergrowth

Magnetic properties, microstructures and chemical composition of magnetite from Yanahara mine, Okayama Prefecture were measured using a SQUID magnetometer, EPMA, and Mossbauer spectroscopy. The high coercivity of the magnetite is not due to secondary low temperature oxidation, but is considered to be due to the primary composition and microstructure.