Oldest Rock in the United States — 3.524 billion years old
Outcrop of the Morton Gneiss west of Morton, Minnesota.
Morton Gneiss used as rough-cut stone that covers the exterior of the Zion Lutheran Church, Morton, Minnesota
Morton Gneiss used as facing stone at the corner of Main Street and West Second Street (Highway 19) in Morton, Minnesota.
Close-up of the black-and-pink swirls in the Morton Gneiss on a building on West Burnside Street in Portland, Oregon.
Morton Gneiss used as countertops at the McDonald's in Redwood Falls, Minnesota.
Morton Gneiss covers the exterior of the Adler Planetarium in Chicago.