Ferro-manganese encrustation on the tympanic bulla of a minke whale from Central Indian Ocean Basin

Abstract

Ear bone of a minke whale (<i>Balaenoptera acutorostrata</i>) was collected from 5200 m water depth with thin coating of Fe-Mn oxide on its surface. The Fe-Mn coating material was similar in nature and ratios Mn/Fe and Cu + Ni/Co were closely comparable to Fe-Mn nodules of Central Indian Ocean Basin. The enrichment of Mn, Co, Ni, Cu within the fresh part of the specimen might be due to the replacement of Ca by Mn⁺⁴, Co⁺², Ni⁺², Cu⁺² in carbonate hydroxy apatite structure and or due to the easy path available for the movement of these metal ions through collagen fibrils and ultimate concentration and deposition within the gaps of collagen.