Cobalt is found across a surprisingly wide range of places, from deep underground mines in Central Africa to the rechargeable battery in your pocket. It’s the 33rd most abundant element in the Earth’s crust, present at an average concentration of about 20 to 25 parts per million. But cobalt rarely exists on its own. Almost all of it is extracted as a byproduct of mining other metals, and it shows up in trace amounts in soil, seawater, and even the food you eat.
The Earth’s Crust and Soil
Cobalt occurs naturally in rocks and soil worldwide, typically at low concentrations. The average in the Earth’s crust sits around 17 to 25 parts per million, depending on the source and measurement method. That makes it roughly as common as lithium and more common than tin, but far less concentrated than metals like iron or aluminum. It tends to be bound up in mineral ores alongside nickel, copper, and arsenic rather than forming pure cobalt deposits.
Soils inherit their cobalt content from the underlying bedrock. Volcanic and sedimentary rocks rich in iron and magnesium tend to produce soils with higher cobalt levels. In some agricultural regions, cobalt-deficient soils are a known problem because grazing animals need trace amounts of it to produce vitamin B12 in their gut.
Where Cobalt Is Mined
The single most important source of mined cobalt on Earth is the Central African Copperbelt, a massive geological formation stretching across the southern Democratic Republic of Congo (DRC) and into Zambia. The cobalt-bearing ores here sit within a rock sequence called the Katanga Supergroup, which formed roughly 550 to 560 million years ago. Major mining operations run from Kolwezi to Likasi in the DRC’s Katanga province, and the deposits rank among the largest metallogenic provinces in the world.
The DRC dominates global production. In 2023, the country produced an estimated 170,000 metric tons of cobalt, accounting for about 74% of the world’s total mine output. The runners-up are far behind: Indonesia produced 17,000 metric tons (7%), followed by Russia at 8,800, Australia at 4,600, and Madagascar at 4,000.
Reserves tell a slightly different story. Australia holds the largest known cobalt reserves at roughly 1.7 million metric tons, while the DRC holds about 6 million metric tons. The global total sits around 11 million metric tons. But reserves only matter if they’re economically viable to extract, and the DRC’s ores are unusually rich and accessible compared to deposits elsewhere.
One critical fact about cobalt mining: approximately 99% of all cobalt is produced as a byproduct of copper or nickel operations, not from dedicated cobalt mines. In 2022, about 74% came from copper mines and 25% from nickel mines. Only around 1% was extracted from mines where cobalt was the primary target. This means cobalt supply is tightly linked to demand for other metals, making it vulnerable to price swings and supply disruptions that have nothing to do with cobalt itself.
Inside Batteries and Electronics
If you’re holding a smartphone, you’re holding cobalt. Lithium-ion batteries use cobalt in their cathodes, the positive electrode that stores and releases energy. In electric vehicle batteries, cobalt can make up to 20% of the cathode’s weight. A single 100-kilowatt-hour EV battery pack can contain up to 20 kilograms of cobalt. Smartphones need far less, just a few grams per device, but the sheer number of phones manufactured each year adds up.
Cobalt helps batteries hold more energy in a smaller space and improves their thermal stability, reducing the risk of overheating. This is why it became so central to the rechargeable battery industry. However, its cost and the ethical concerns around mining in the DRC have pushed manufacturers to develop battery chemistries that use less cobalt or none at all. Lithium iron phosphate batteries, which contain no cobalt, are gaining market share in both EVs and grid storage.
Other Industrial Uses
Beyond batteries, cobalt shows up in a range of industrial products. Superalloys containing cobalt are used in jet engine turbine blades and gas turbines because they maintain their strength at extreme temperatures. Cobalt compounds produce the distinctive deep blue color in glass, ceramics, and pottery, a use that dates back thousands of years. It’s also a key ingredient in hard-wearing cutting tools and drill bits, where cobalt serves as a binding agent in tungsten carbide composites. Magnets made with cobalt alloys are used in sensors, motors, and military applications.
In Food and Your Body
Cobalt is an essential trace nutrient for humans, but only in one very specific form: as the central atom in vitamin B12 (cobalamin). The molecule is one of the most structurally complex small molecules found in nature, built around a cobalt ion nested inside a ring structure called a corrin macrocycle. Without that cobalt atom, B12 cannot function.
Humans get their cobalt almost entirely through dietary B12, primarily from dairy products and meat. Your body doesn’t need cobalt in any other form, and pure cobalt compounds can actually be toxic in large amounts. The cobalt in B12 supports red blood cell production, nerve function, and DNA synthesis. Deficiency leads to the well-known symptoms of B12 deficiency: fatigue, nerve tingling, and anemia.
Recovering Cobalt From Recycled Batteries
As millions of lithium-ion batteries reach the end of their useful life, spent batteries are becoming an increasingly important secondary source of cobalt. Modern recycling techniques can recover cobalt with impressive efficiency. Lab-scale processes using specially designed solvents have achieved cobalt recovery rates of 90% to 97% from used battery cathode materials, with some methods working at relatively mild temperatures in as little as 20 minutes.
Scaling these processes up to handle the growing wave of retired EV batteries is one of the major challenges in the cobalt supply chain. If recycling can be made economically competitive with mining, it could significantly reduce pressure on primary cobalt sources and the environmental and human costs associated with extraction in the DRC.