Tertiary basalt flows from west Greenland commonly contain metallic iron and graphite. They are thus some of the most reduced of terrestrial basalts, and are of interest in connection with basalt studies in general, and in connection with the origin of certain meteorites (Lovering, 1964). Xenoliths composed mainly of plagioclase (An_70-75), graphite, rose-colored spinel and rarely corundum are included in these basalts on Disko Island. The xenoliths are remarkably similar to reconstituted shale xenoliths in basaltic rocks from other localities except for the presence of graphite and in the composition of the spinel. The spinel has n=1.747 ± 0.001, a=8.119 ± 0.002 and D=3.81 ± 0.01, and electron microprobe analysis gave Mg=13 and Fe=8.9per thousand. These data indicate a spinel with composition about Sp₇₈He₂₂. This unusually low Fe content compared to spinels from other aluminous xenoliths in basaltic rocks is evidently related to the low oxygen fugacities in basaltic magmas in contact with graphite, particularly in an environment such as Disko, where active reduction of ferrous iron to iron evidently occurred. The close similarities in the mineralogy of the xenoliths from specimen to specimen indicate complete equilibrium of magma and xenoliths. This equilibrium involved mainly loss of kinds of K and Si, and gain of Ca, Mg, Al and Na by the xenoliths. The xenoliths in their similarities to known reconstituted shale xenoliths, their graphite content, and low-iron spinel substantiate the idea of derivation of the metallic iron by near surface reduction of basaltic magma by carbonaceous sedimentary rocks (Törnebohm, 1878; Steenstrup, 1882), rather than derivation of the metallic iron from the mantle (Lindgren, 1933; Urey, 1952).