The Mesoproterozoic St. Francois Mountains (SFM) terrane of southeast Missouri, USA contains examples of both iron oxide-apatite (IOA) and iron oxide-copper-goldcobalt (IOCG) deposits that yield clues concerning processes controlling metal endowment in iron oxide systems. The SFM terrane lies within the Eastern Granite-Rhyolite Province along the Paleoproterozoic margin of the Mazatzal Province of the Laurentia craton (fig. 1). The province formed from juvenile additions to the crust during two major pulses (<50 m.y.) of igneous activity: (1) an older (ca. 1.501.44 ga) episode of volcanism and granite plutonism and (2) a younger (ca. 1.331.30 ga) episode of bimodal gabbro and granite plutonism. all known iron oxide mineral deposits are hosted in the older volcanic and associated hypabyssal intrusions; no identified mineralization occurs in the younger bimodal plutons. the sfm formed as a result of reworking of relatively young materials along the margin of the laurentian craton caused by mantle-derived mafic underplating and melting of the craton to generate the igneous rocks and associated ore-forming hydrothermal fluids. citation: day, w c, dubray, e a, mccafferty, a e, hofstra, a h, aleinikoff, j n, johnson, c a and ayuso, r a, 2019. character and paleotectonic setting of mesoproterozoic iron oxide deposits of the st. francois mountains, missouri, usa, in proceedings pacrim 2019, pp 159161 (the australasian institute of mining and metallurgy: melbourne).>