A logging camp known as Splitrock existed at the mouth of the Split Rock River from 1899 to 1906. Pilings from their dam and wharf are still visible jutting from the water. The Merrill Logging Trail follows the route of their rail line. In 1901 a prospector from Duluth misidentified the outcrops of anorthosite as corundum, an extremely hard mineral valuable as an industrial abrasive. Three years later the North Shore Abrasives Company set up mining operations on Corundum Point, but abandoned the site in 1908 when their product was found to be inadequate. Their crushing house burned down in a forest fire in 1910 but its concrete footings remain.