Magnetite partition coefficient

Protactinium partition coefficients cannot be estimated with any degree of accuracy from the available data. However, from a compilation of 40 magnetite-melt pairs where... 

Ilmenite. There are currently no experimentally-determined ilmenite-melt partition coefficients. We must rely instead on phenocryst-groundmass data analyzed by PIXE (Stimac and Hickmott 1994 Ewart and Griffin 1994). Like magnetite, ilmenite is characterised by two relatively small sites, and is therefore unlikely to take up appreciable amounts of lanthanides or large alkaline earths. We will confine ourselves again to U, Th and Pa. 

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