SIOUX FALLS, S.D. (KELO) — Following the discovery of a large deposit of concentrated critical minerals in North Dakota, including samples of cobalt, gallium, lithium and germanium, KELOLAND News reached out to experts at South Dakota Mines to find out if such a supply could exist here as well.

KELOLAND spoke with Jon Kellar, Professor of Materials and Metallurgical Engineering and William Roggenthen, Professor Emeritus of Geology and Geological Engineering.

Before digging into the reality of critical mineral deposits in South Dakota, it’s important to reflect on a point made by Roggenthen, that Rare Earth minerals and critical minerals are not the same.

Rare Earth elements, notes Roggenthen, are specifically defined, they have their own space marked out on the periodic table, and consist of the following:

  • Scandium
  • Yttrium
  • Lanthanum
  • Cerium
  • Praseodyium
  • Neodymium
  • Promethium
  • Samarium
  • Europium
  • Gadolinium
  • Terbium
  • Dysprosium
  • Holmium
  • Erbium
  • Thulium
  • Ytterbium
  • Lutetium

While it is entirely possible for a Rare Earth mineral to be defined as a critical mineral, critical minerals have a more flexible definition.

This, explains Kellar, is due to how critical minerals are defined, or rather, by who defines them. In the U.S., critical minerals are defined by the federal government, and are minerals determined to be ‘critical’ to the security of the nation.

These minerals may receive this designation by the U.S. Department of Energy, who may judge a mineral to be vital for the nation’s energy security, for instance, or by the U.S. Department of Defense, who may need it for use in military components or to uphold a supply chain, explains Roggenthen and Kellar.

The importance of these minerals and the amount of resources dedicated to uncovering them are dependent on how critical they’re judged to be. Some of these critical minerals used to just be minerals, noted Kellar.

South Dakota does have some of these minerals, confirmed Roggenthen and Kellar, mentioning deposits of lithium in the southern Black Hills, the Rare Earth ore deposit in the northern hills, and a massive range of manganese ore spread throughout central and eastern South Dakota.

Despite the knowledge of these deposits, the pair say that right now, there is virtually no significant extraction of critical minerals happening in South Dakota.

In part, this is due to the relative recency of these minerals becoming more critical. Your cell phone, for instance, is chock full of critical minerals, and the current supply of these is diminishing, and not readily available in the U.S.

While we are aware of deposits of such minerals in South Dakota, extraction of them is potentially still far out, requiring not just permitting and infrastructure, but also greater exploration.

One of the questions that such exploration must answer is this: Do the critical minerals present in South Dakota occur in such concentrations that make them feasible to extract and process?

South Dakota’s manganese supply is a good example. As noted by Kellar, manganese is critical due to its use in manufacturing of modern steel.

South Dakota has a large quantity of manganese spread throughout the central and eastern parts of the state, but the question is whether there is enough of it in one area to justify mining.

You can think attempt to visualize this issue by picturing a sand box containing a large number of grains of salt. While there may be a lot of salt amid the sand in the box, if it is all dispersed throughout the entire sand box, extracting it will be almost impossible. However, if all that salt is concentrated together into a few lumps of veins buried in the sand, extracting and processing it suddenly become much simpler.

Luckily for the various scientists responsible for this type of exploration, there is more to it than simple drilling into the ground and seeing what’s there.

Many of the minerals sought after were formed by conditions millions of years ago, a time when what is now South Dakota lay beneath a Cretaceous era sea. By understanding this ancient geology and how the elements present at the time interacted, scientists today can get an idea of just where to look for things such as critical minerals.

Another indication of mineral wealth can also be the discovery of deposits nearby. Roggenthen notes interest in mineral exploration in northwestern South Dakota. This area is geographically similar to the area in North Dakota where critical mineral concentrations were just discovered. It’s also geographically nearby.

One other advantage South Dakota has in the growing mineral field, beyond the presence of minerals, is South Dakota Mines itself.

“We are one of only five universities in the nation who have all the disciplines– Geology/Geological Engineering + Mining Engineering + Metallurgical Engineering / Materials science,” said Mines communications manager Mike Ray in an email to KELOLAND News. “This makes us extremely unique in being able to help the nation secure critical minerals in a way that does not harm the environment.”

Harm to the environment is absolutely a major concern that arises when considering the extraction of critical minerals, a process which Kellar notes is not always done ethically or sustainably in many parts of the world outside of the U.S., Canada and Australia.

This concern grows considerably when the prospect of mining for material in the Black Hills, home to a National Forest and federal and state park areas, and an area that a large population of indigenous people considers sacred.

Despite these concerns, Kellar believes that mining of such elements as lithium can be done without causing damage to the environment of the Black Hills, noting that many mines currently operate in the region without much notice from those living around them.

The will to pursue such action, of course, goes back to the importance put on the minerals in question. The more critical the mineral is judged to be for concepts such as ‘national security’ the more resources will be directed toward moving toward extraction.

While there is not currently critical mineral extraction taking place in South Dakota, Kellar speculates that, depending on how quickly the need for these materials grows, such a reality may not be far away.

“For that to happen we will need to see more exploration into the concentrations of minerals in the state. To simplify it, we currently know the minerals are there, but have yet to find out if they can be extracted and if they can be processed into the material needed for production,” Kellar said.