The surrounding area was once used for mining clay that made possible the pottery industry founded with John Paul after the land was purchased to supply the needed material. The clay was found at depths of four to twenty-five feet or more and occurred in three grades: Number 1, a gray clay with no impurities that was limited in quantity; Number 2, also gray, which was the most common; and Number 3, a brown clay containing small amounts of sand, shale, and gray clay that was used to produce sewer pipe. Mining began with clearing topsoil, digging out the clay, and loading it by hand before steam-powered drag-lines replaced that work. The clay was first hauled by horse and wagon to Red Wing, then carried by a rail spur built by the Duluth Red Wing and Southern Railroad Company, which operated from 1892 until its abandonment in 1936. Thousands of carloads of clay were transported to Red Wing for the production of stoneware and sewer pipe. Over the years the pits closed and reopened, other nearby pits were opened, diesel equipment replaced steam-powered machinery, and trucks replaced trains. By the 1970s mining and pottery operations had ceased after years in which the industry employed many men and women, gave many newly arrived emigrants, mostly Scandinavian, their first jobs during the county's early industrial development, and brought recognition and fortune to the area.