Abstract <p>Detailed mineralogical and petrogeochemical studies of gabbro–dolerites of the Dlinnoe ore occurrence (Pai-Khoi, Nenets Autonomous District, Russia) were carried out. Three main rock types are identified within the ore occurrence: (1) porphyritic quartz-bearing fine- to medium-grained gabbro–dolerites, (2) quartz medium- to coarse-grained gabbro–dolerites, and (3) leucocratic quartz fine-grained gabbro–dolerites (3) with schlierens and lenses of medium- to coarse-grained diorites. Petrographic and petrochemical studies suggest that the rocks have formed as a result of differentiation of a single magmatic melt, with porphyritic quartz-bearing gabbro–dolerites of the eastern part being early differentiates and quartz and leucocratic gabbro–dolerites and diorites of the western part being late formations. In early differentiates—quartz-bearing gabbro–dolerites—sphalerite–pentlandite–chalcopyrite–pyrrhotite schlierens and nested disseminated mineralization was identified. Telluride, bismuthotelluride and sulfoantimonide mineralization also gravitates to these rocks. Late differentiates—quartz gabbro–dolerites—are associated with pyrite–sphalerite–chalcopyrite–pyrrhotite nested and vein-embedded mineralization. Hessite, altaite, melonite, vavřínite, volynskite, kochkarite, rucklidgeite, and ullmannite were detected for the first time at the ore occurrence. For the first time, Raman spectra for volynskite and kochkarite were obtained by spectroscopic methods, and the determination of rucklidgeite and vavřínite was confirmed by Raman spectroscopy. It was noted that the greatest diversity of mineral species is characterized by early differentiates, where Ni content prevails over Co.</p>