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We conducted a systematic study of oxide minerals in LL3.0-6 chondrites, and found ilmenite, rutile,perovskite and an unknown A1-Ti-Zr-oxide. Ilmenite is low in abundance, but is present in the chondrules and matrix of all the samples that we studied. The MnO content of ilmenite in LL3.0-3.3 is lower than that in LL3.5-6. The low concentration of MnO in the former is due to crystallization from chondrules melts at high temperatures. On the other hand, ilmenite composition in LL3.5-6 reflects thermal metamorphism. Therefore, ilmenite is indicative of petrologic type.We also made the first measurements of the 53Mn-53Cr systematics of ilmenite in ordinary chondrites. The age for ilmenite in Y790256 (LL6) is determined to be about 2 Ma older than angrites. This may represent the metamorphic age of the LL chondrites.