R4: Mineral sciences of the Earth surface

[R4-08] Mineralogical study of manganese-rich tissue in radular teeth of chitons

*Koji Ichimura¹, Toshihiro Kogure¹ (1. UTokyo)

Keywords:biomineral, manganese, magnetite, EPMA, FIB-TEM

A manganese-rich tissue found in the lower-posterior part of radular teeth of some chitons was investigated mineralogically. The tissue in Placiphorella stimpsoni contains 50-55, 8-9, 4-7 wt% of iron, manganese, and copper, respectively. From a result of FIB-TEM, it was composed of aggregates of spinel crystals with a size of 10-30 nm, with no preferred orientation. This study will extend new findings on the relationship between transition metals and biomineralization.