Fe-Mg M1 site distribution in some clinopyroxenes from Santa Olalla (Huelva, Spain)

Abstract

The crystal structures of two clinopyroxenes related to the skarns from Santa Olalla (Huelva. Spain) have been refined. From these refinements it is shown that pyroxene SO-1 of metamorphic origin is almost pure diopside. whereas for pyroxene SO-2 of metasomatic origin the following formula CaMg 0.64 Fe 0,34 Si2 O6. was found. These clinopyroxenes show cation ordering.