Critical Minerals
and Materials

Step 1: Find and Characterize

Recovering mineral sources begins with data. Before critical minerals are recovered from the earth, geologists must survey and sample to understand whether extraction is technically possible and economically feasible. Without those details, projects can’t be planned, financed, or permitted. Early assessment also helps determine which processing routes come later.

But even once they’re found, critical minerals aren’t formed or deposited uniformly. They’re often concentrated. Localized geological processes make it so one mineral may be abundant in just a few regions. And even then, that mineral may be clustered, formed along a narrow vein of mineral-rich rock.

Pacific Northwest National Laboratory (PNNL) researchers are working to more quickly and efficiently identify where critical minerals and materials can be harvested. Drawing on decades of experience in chemistry and subsurface science, PNNL scientists use special techniques to “peer” below Earth’s surface. Subsurface sensors can detect geophysical signatures that reveal mineral-rich deposits. Measurements like these create data, and data help us to understand where our retrieval efforts are best focused. Leveraging high-performance computers, scientists process these data, generate images of the subsurface, and help to understand where minerals are hiding in microscopic rock pores.

Step 2: Recover and Separate

Once a mineral resource is proven and plans are approved, extraction begins. Different minerals require different approaches. In conventional mines, ore—a naturally occurring solid material in which minerals are chemically embedded—is separated from waste rock. Depending on the material, ore may be crushed and ground into a fine powder before target minerals are separated and purified. 

Separating one compound from another can happen physically, like running coffee through a filter. It can also happen chemically, like separating caffeine from coffee beans. Nickel, for example, is isolated using magnets, smelting, and chemical agents like hot sulfuric acid. PNNL scientists are helping to uncover new separation techniques specially tailored to critical minerals. By exploring how critical minerals and materials respond under a wide web of conditions, they can offer up a range of cost-saving techniques to pull valuable materials from complex mixtures.

Not every one of the 60 U.S.-recognized critical minerals come from mines. Magnesium has been extracted from seawater for decades. PNNL researchers are working to recover other valuable minerals from seawater and seaweed, as well as wastewater and waste rock. Even mineral-binding algae could help with alternative approaches to extraction—another approach pursued by PNNL scientists—perhaps providing biofuel along the way.

For example, in lieu of the large, open-surface mines we tend to think of, our scientists envision much narrower, less invasive mines. Instead of a mining shaft large enough for miners, equipment, and ore to fit through, imagine a slender well in which engineered fluids flow down. Those fluids react with rock and “mobilize” the minerals, freeing them to be pulled to the surface in liquid form.

Step 3: Process and Manufacture

Processing, purifying, refining, and in some cases metallizing produces materials that are then transformed into components for electronics and other products. For example, metals may be converted into powders, thin films, alloys, or electrode materials. These inputs are then shaped and combined through manufacturing steps like casting, rolling, machining, or coating. Finally, finished parts are assembled into devices, completing the path from raw mineral to the technologies people rely on.

At PNNL, researchers are working to make this manufacturing more efficient and economical, so we may reduce or replace critical mineral dependence. Our scientists are figuring out how to make mineral-dependent materials with fewer, less pure, or completely different minerals. One development includes a manganese-based superalloy that dials down U.S. reliance on cobalt: a long-favored, often imported ingredient for metals that must endure extreme environments like the interior of nuclear reactors.,

From the earth to the phone in your hand, each step along this journey represents a step inside the critical material supply chain.

Each of these steps can happen in a different place on the planet; recovery in one country, processing in another, and manufacturing elsewhere. Every step holds wide-ranging implications, from the environmental consequences of harvesting to the economic influence of manufacturing.  

PNNL scientists are working to map this intricate web, to better understand the interconnectedness of the supply chain’s every variable. When we can fully model the critical material supply chain, we can make informed decisions about mitigating risk, bolstering national security, and strengthening our own domestic supply chains.