Carbon mineralization is the process of storing carbon dioxide by reacting it with magnesium and calcium to form carbonates. Magnesium and calcium are often found in mine tailings, making them an attractive feedstock for carbon mineralization. Furthermore, mine tailings also contain critical elements, such as cobalt and nickel, which are critical for the energy transition, as they are key elements in technologies such as electric vehicles, batteries, and more. Critical element extraction is the process of removing these elements through two major steps: acid leaching and standardized precipitation. The current acid leaching method is used to extract critical elements, magnesium, and calcium from the mine tailings into a leachate solution. The solution’s pH is then changed to selectively precipitate out iron and nickel, leaving behind magnesium and calcium to be reacted with CO2. In this way, critical element extraction can be integrated with the carbon mineralization process, seeing that the output of critical element extraction can be the input for carbon mineralization. However, precipitation requires large volumes of base, which increases the cost and associated emissions of the overall process. A potential solution is to use magnetic separation to extract the iron; before placing the tailings in acid, a magnet can be moved around a solution of tailings to remove as much iron as possible before the acid-leaching steps. In this experiment, we evaluated the benefit of the magnetic separation step in critical mineral extraction on mine tailings from the Stillwater mine in Montana. After comparing the efficiency of iron removal, we determined that the mine tailings contained a far greater percentage of magnetic material than previously anticipated; this difference proves that the magnetic separation method is highly effective, but it caused inconclusive results in terms of extraction efficiency improvement. Further experiments and analysis should be conducted to continue evaluating the extractive and economic benefits of magnetic separation. These results are significant because they provide a way to supply metals critical for the energy transition, make mining more sustainable, and store carbon dioxide, which can be a tool to meet global climate goals.