There’s a lot of interest in what are called “rare earth elements.”
They have been found in North Dakota’s lignite deposits.
"They're 14 different elements," said North Dakota state geologist Ed Murphy. "They make very strong, and relatively small, magnets."
Murphy said they're used in things such as cell phones, solar technology and wind turbines.
"Every time we go out, we find a little bit higher levels of those rare earth elements," Murphy said. "We have found the highest concentration of those elements in coal in the nation."