The Duluth Complex, Minnesota, an exposed, mafic plutonic pan of an aborted 1.1 Ga intracontinental rift, is broadly subdivided into an older anorthositic series and a younger troctolitic series. It was intruded into a dynamic rifting environment beneath a thick tholeiitic lava pile and above older country rocks ranging in type from pelitic metasediments and banded iron formations to granite-greenstone complexes. The basal troctolites of the Duluth Complex contain a large, low-grade Cu-Ni sulfide resource and several platinum group element (PGE) occurrences. The ranges of PGE and Au concentrations in the troctolitic rocks are in ppb): Os (<3-15), Ir (<0.1-25.1), Ru (<1-50), Re (<1-13), Pt (<5-390), Pd (5-1300). Locally total PGE concentrations reach >9000 ppb. Chondrite-normalized PGE patterns show two trends, as defined by the presence or absence of a low-Ir anomaly. PGE-enriched (Pt or Pd > 1 ppm) troctolitic rocks have a distinct isotopic signature which consists of ∂³⁴S values < 10 per mil and which extend to lower values than those of the Cu-enriched zones. This suggests a different mechanism for the formation of the PGM-bearing rocks in comparison to the Cu-Ni mineralized rocks. Platinum group minerals (PGM`s) include sperrylite, taimyrite, froodite, michenerite, and moncheite. The PGM`s are associated with serpentinized olivine and secondary magnetite or with altered, calcic plagioclase (-An₇₅), and hydrosilicates. Pd-bismuthotellurides are associated with parkerite tellurobismuthinite, bismuthinite, hessite, native gold and clausthalite, and with low-temperature sulfides such as valleriite, violarite, heazlewoodite, and in some instances graphite. These associations suggest that the PGM`s were transported and deposited during a late-magmatic hydrothermal event related to the introduction of volatiles from the underlying metasediments. The high Cl-content of serpentine, biotite, apatite and graphite, the high An-content of the plagioclase in contact with the sulfides and PGM`s, and the presence of Fe₂(OH)₃Cl in partially serpentinized troctolitic rocks further suggest that a C-H-O-S-Cl fluid acted as a transport mechanism for PGE`s.