IUGS definition of mafic granulite: "High-grade metamorphic rock in which Fe-Mg silicates are dominantly hydroxyl-free; the presence of feldspar and the absence of primary muscovite are critical, cordierite may also be present. The rocks with >30% mafic minerals (dominantly pyroxene) may be called mafic granulites. The term should not be applied to ultramafic rocks, calc-silicate rocks, marbles, ironstones, or quartzites."