Mining companies from around the world are exploring what lies under northeastern Minnesota and are finding some of the largest copper deposits on the planet. Minnesota's lode is estimated at 900 million tons, which would be second only to Russia. With economic growth - especially in China - pushing up demand for copper and other metals, Minnesota is poised for a resurgence of well-paying mining jobs.
Search for Jayme Closs centers on 13-mile stretch west of Barron
The sheriff's office asked for 100 volunteers.