Identification of silicate and carbonaceous presolar grains in the type 3 enstatite chondrites

We surveyed presolar grains in primitive enstatite chondrites by isotopography using the HokuDai isotope microscope system. The mineral identification has been conducted by X-ray analysis with scanning electron microscopy. The chemical compositions are determined for eight silicate and ten carbonaceous presolar grains. Presolar grains of pyroxene compositions are dominant in the enstatite chondrites. This suggests that presolar silicates of enstatite composition were selectively survived in the enstatite chondrite parent body or the enstatite chondrite formation area in the solar nebula.