Morton Gneiss

Morton gneiss, also known as rainbow gneiss, is an Archean-age gneiss found in the Minnesota River Valley of southwestern Minnesota, United States. It is one of the oldest stones on Earth, at about 3.5 billion years old. Along with the nearby Montevideo Gneiss, it is the oldest intact continental crust rock in the United States.[1] Its type locality is in Morton, Minnesota.[2]

Morton gneiss is quarried for monuments and as a facing stone for buildings.[2]

  1. ^ Aber, James S. (2012). "Morton Gneiss, Minnesota". Emporia State University. Retrieved 2019-05-22.
  2. ^ a b Nelson, Paul (2018-03-20). "Morton Gneiss". MNopedia. Minnesota Historical Society. Retrieved 2019-05-22.