Pacolet Soapstone is here named as the basal unit of the Hammett Grove Meta-igneous Suite (new name), a dismembered ophiolite in the northwestern Piedmont of SC. Unit is an altered ultramafite lithodeme consisting of massive and schistose talc-rich rocks and serpentinite interpreted as tectonized peridotite. At the type locality, boulders of massive greenish gray soapstone are composed of talc, tremolite-actinolite, magnetite, secondary serpentine, chlorite, a carbonate mineral, and pyrite. Locally, it comprises tremolite-actinolite schist, chlorite schist, or both. In thrust fault contact with Late Proterozoic and early Paleozoic metamorphic rocks of the Inner Piedmont belt. Presumably underlies South Goucher Metapyroxenite (new name), which represents the cumulate ultramafites of an idealized ophiolite section. No real thicknesses of the Hammett Grove units are known. Author suggests that the Hammett Grove Suite is not only allochthonous, but a thrust slice or klippe of Kings Mountain belt derivation, and documents a middle Paleozoic accretionary event.

Source: GNU records (USGS DDS-6; Reston GNULEX).