Abstract: | Electron microprobe analyses and petrographic observations demonstrate that Almelo Township (L6), Beeler (LL6), Kalvesta (H4), Phillips County (L6), and Yocemento (L5) are typical ordinary chondrites. Selden has abnormally iron-rich silicates and nickel-rich metal, and it may have been a lower petrologic type that has been shocked to an LL5. Shielding corrected exposure ages range from 0.80 m.y. (Kalvesta) to 47.0 m.y. (Yocemento). |