Rare Set of Three United States Geological Survey (USGS) Copper Map Plates, each of the three engraved plates illustrating a topographical map of Madison Parish, Louisiana, including its plantations and the oldest Native American earthen mounds in the U.S., surveyed at the scale 1:24,000, each plate 17" x 20", overall weight 37.5 lbs. Last year the Federal Government released to the American public for sale thousands of hand-made copper engraving plates used by the United States Geological Survey (USGS); the rest were gifted to major institutions and universities. The plates, produced between 1880 and 1950 in sets of three, were used to produce topographic and geologic maps of various regions and cities in the United States: one plate, inked in black, denoted cultural features and text; another inked in blue illustrated bodies of water; and a third printed in brown ink delineated topographical contours. Each quadrangle plate (produced in mirror image for printing purposes) was etched by a USGS cartographic engraver, and contains historic and scientific information, including cultural transportation, boundary features, hydrography and geology. The extraordinary crispness of these plates has been preserved, as the plates themselves were not actually used to make the maps, but instead, were transferred to a large lithographic stone in order to make multiple prints. These stunning copper plates are truly rare American memorabilia; they are both historical records and veritable works of art.