The Precambrian geology and talc deposits of the Balmat-Edwards district, northwest Adirondack Mountains, New York

The Balmat-Edwards, or Gouverneur, mining district is in the Grenville Lowlands of the northwest Adirondacks, St. Lawrence County, New York. In the district, important deposits of talc and zinc and minor deposits of lead are mined from a northeast trending belt of marble. Deposits of pyrite that were prospected and mined during and before World War I occur in schists in the vicinity of Pyrites and Antwerp villages. Fifteen to 50 miles east-southeast is the St. Lawrence County magnetite district, which contains commercially important magnetite deposits.