About 1% of the volume of NWA 869 L3-6 is impact melt rock (IMR) according to Metzler et al. Their study tells us a lot about these highly variable fine grained inclusions we find in cut stones. Some IMR clasts include mineral and rock clasts, some do not. The crystallized fallback material is depleted in nickel-iron metal and sulfides. Grains that crystallized from the melt are olivine. Any pyroxene crystals are included relict grains. Oxygen isotope analysis show that some IMR match bulk sample values while some do not. The latter perhaps reflect inclusion of impactor material.
These photos are of two nearly adjoining IMR inclusions in one thin section.
