Abstract: The chemical, mineralogical,structural, morphological characteristics of KTB spinelbearing spherules,and the experimental results of meteorite ablation,are suggestive of that some of KTB spherules derived from projectile ablation debris,some from condensates of impact vapor.More than these,some KTB spherules are of the characteristics in compositions similar to that of condensates of impact vapor but in structures similar to that of projectile ablation debris suggesting that these spherules might be derived from another mechanism.