The pyroxenes and olivines in the two fragments vary widely in their Mg/Fe ratio and include highly Fe-rich compositions for lunar basalts (data S1). The mineral chemistries of these two fragments differ slightly and appear to correspond to their textures (data S1). For example, the olivine in CE5-B2 is more Fe-rich whereas CE5-B1 has a wider range of TiO2, Al2O3, and Cr2O3 in pyroxene (data S1). The mineralogy of these fragments is similar to that of other known lunar basalts. The K-rich glass and the presence of Zr-bearing minerals raise the possibility of a mantle component enriched in heat-producing elements, but these basalts appear to be compositionally fractionated, so the presence of these evolved minerals may instead reflect a small degree of partial melting and/or extensive fractional crystallization.