Mesabi Nugget LLC (81 percent-owned by Steel Dynamics, Inc.) produces iron nuggets principally as feedstock for EAF steelmaking, but the product may ultimately be useful to other consumers of iron. Currently nuggets are not offered for external sale. Our Indiana and Mississippi steel mills consume all the iron nuggets produced.
Created using an innovative proprietary ITmk3® process licensed by Kobe Steel, Mesabi nuggets are elliptical in shape and about a half inch in diameter. They are 96 to 98 percent pure iron with the remainder primarily carbon. The nuggets are inert, allowing them to be easily handled and transported.
Mesabi Nugget production process
The ITmk3® process converts “dry balls” composed of iron fines, pulverized coal, fluxes, and binders to iron nuggets using a direct-reduction process in a natural-gas-fired rotary hearth furnace. This process utilizes iron concentrate processed from low-grade iron deposits from the Minnesota Iron Range. This direct reduction of iron is more energy-efficient and more environmentally friendly than traditional iron-making processes.
ITmk3® is a registered trademark of Kobe Steel, Ltd.
Annual production capacity