Read/Search this Article
The Yamato (Y)-691 chondrite includes unusual silicate-inclusions besides chondrules. An inclusion containing high CaO and Al_2O_3 contents and other opaque massive inclusions containing high FeO content are similar in bulk chemical compositions to fine-grained CAI's and amoeboid olivine inclusions in carbonaceous chondrites, respectively. They are concluded to be melted finegrained CAI's and melted amoeboid olivine inclusions. Most unusual inclusions containing high FeO content were originally high-temperature condensates under oxidized conditions and followed by melting events. After the consolidation, they were brought into extremely reduced conditions, where they accreted with magnesian chondrules on a parent body of the Y-691 enstatite chondrite.