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(Unfug Ridge). Olivine Titanaugite Basalt. This rock is holocrystalline, porphyritic-aphanitic, with fine- to medium-grained subhedral to euhedral phenocrysts in a grey-green groundmass (10%) composed of fine-grained mica and opaques. All crystals are subhedral except fluorite (<1 mm), spherulites (.5-1 mm), which are anhedral. Olivine (.5-2 mm) and opaque minerals (<1 mm) are subhedral to anhedral. Fluorite occurs after iddingsite. The following are present as phenocryst phases: Olivine (.5-2 mm) is present with some crystals altering to serpentine; titanaugite and orthopyroxene (1-2 mm); orthoclase (<= 1mm); apatite (<.1 mm); zircon (<.1 mm); analcite (<.1 mm); biotite (<.1 mm). Stellate clusters of titanaugite are moderately common. Some of the titanaugite exhibits hourglass zonation.