Sulfide and oxide mineralization occurs along the western and northern footwall contacts of the 1.1-Ga Duluth Complex (Complex) in northeastern Minnesota, which was emplaced during the formation of the Midcontinent Rift System. Platinum-group element mineralization is known to occur only along the western contact. The Duluth Complex is composed of troctolitic, gabbroic, and anorthositic rocks that form a series of individual intrusions that make up the Complex. These were emplaced into footwall rocks of Archean granite-greenstone terranes and Lower Proterozoic metasedimentary rocks (Biwabik and Gunflint Iron-Formations; Rove, Virginia, and Thomson Formations) and into the penecontemporaneous North Shore Volcanic Group basalts, which form the hanging wall, and, in some areas, the footwall. Development of riftrelated structures, both extensional and contractional, affected development of mineralization. Structural discontinuities provided conduits for emplacement of late-stage granophyric and pegmatitic iron-rich ultramafic rocks. Faults and folds were responsible for localizing massive sulfide mineralization, as well as, for providing conduits for later syn-to post-magmatic hydrothermal fluids.On the northern margin of the Complex, 81.6 million tons of low-grade titaniferous magnetite ore (approximately 12 to 14% TiO 2 ) occur in 14 bodies that range in size from 1 to 19 million tons. Oxide mineralization along the western contact contains 245 million tons of ≥10% TiO 2 . These include the Wyman Creek area, Longnose, Longear, and Section 17 bodies of the Partridge River Intrusion, and the Water Hen Intrusion of the southern Duluth Complex. Overall three types of oxide mineralization occur in the Duluth Complex: (1) oxide-rich metasedimentary inclusions in mafic or ultramafic rocks that exhibit metasedimentary textures and/or can be traced laterally into footwall iron-formation; (2) banded or layered oxide segregations that include cumulus oxide-rich horizons; and (3) late discordant oxide-bearing ultra-