Nielsenite, a rare intermetallide of palladium and copper, was described previously as a late-magmatic formation. A different genetic type of nielsenite was studied in the layered ultrabasite–basite Yoko-Dovyren intrusive. The maximum concentrations of Pd, Pt, Au, and Ag minerals are confined to crosscutting bodies of pegmatoid sulfide-bearing anorthosites within the contact zone between the troctolites and overlapping gabbro-norites strata in this intrusive. Postmagmatic pneumatolytic (fluid-metasomatic) Pd, Pt, Au, and Ag minerals, such as kotulskite, moncheite, michenerite, zvyagintsevite, telargpalite, paolovite, electrum, and sperrillite, compose metasomes in Fe–Ni–Cu sulfides and in the silicate matrix nearby. The Yoko-Dovyren intrusive is tectonized and tilted, crossed by inclined faults with streamlined serpentinized rocks, which contain lizardite, antigorite, clinozoisite, chlorite, actinolite, prehnite, pectolite, and hydrogarnet and are often transformed into rodingites of a prehnite–pumpellyite facies. The serpentinization process is younger than the intrusive rocks by 55 million years. In metamorphosed anorthosites, chalcopyrite is replaced by bornite, chalcocite, digenite, and magnetite; pentlandite is replaced with violarite, heazlewoodite, …; pyrrhotine is replaced by magnetite, …; moncheite is replaced with cuproplatinum–tulameenite; the veins of clinozoisite and pectolite with chlorite inclusions of chalcosine and native copper are well developed. Curved veins of nielsenite in brecciated chalcopyrite occasionally extend such veins. The size of the veins of metamorphogenic-hydrothermal nielsenite reaches up to 200 × 10 microns. Nielsenite metasomes up to 12 microns in diameter are developed nearby. The composition of the Yoko-Dovyren nielsenite is stable and close to stoichiometric with the formula Pd1.01Cu2,81Fe0,17Ni0,01. The Yoko-Dovyren nielsenite differs from the holotype of nielsenite of the Skergaard intrusive by the absence of Pt and Au impurities and a significant impurity of Fe. Yoko-Dovyren nielsenite was likely to appear under conditions of the prehnite–pumpellyite metamorphism facies at a high fugacity of О2 and at an extremely low fugacity of sulfide sulfur (log f S2 < –24 at ≈300°C).

中文翻译：

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贝加尔湖地区北部贝加里德山脉 Yoko-Dovyren 侵入体含硫化物斜长岩中的变质-热液镍锆石，PdCu3

Nielsenite 是一种稀有的钯和铜金属间化物，之前被描述为晚期岩浆地层。在层状超基石-基石 Yoko-Dovyren 侵入岩中研究了不同成因类型的镍锌矿。Pd、Pt、Au 和 Ag 矿物的最大浓度被限制在这个侵入岩中的 troctolites 和重叠辉长岩-norites 地层之间的接触带内的含有伟晶状硫化物的斜长岩的横切体中。岩浆后气溶（流体-交代）Pd、Pt、Au 和 Ag 矿物，如 kotulskite、moncheite、michenerite、zvyagintsevite、telargpalite、paolovite、electrorum 和 sperrillite，在 Fe-Ni-Cu 硫化物和硅酸盐基质中组成交代体附近。Yoko-Dovyren 侵入岩构造倾斜，被倾斜断层与流线型蛇纹岩相交，含有蜥蜴岩、叶蛇纹石、斜长石、绿泥石、阳起石、葡萄石、胶凝石和水石榴石，通常转化为葡萄石-菱镁矿相的菱形石。蛇纹石化过程比侵入岩年轻 5500 万年。在变质斜长岩中，黄铜矿被斑铜矿、辉铜矿、褐铁矿和磁铁矿取代；pentlandite 被 violarite, heazlewoodite, ... 取代；吡黄铁矿被磁铁矿取代，……；moncheite被铜铂-tulameenite取代；斜长石和绿泥石内含绿泥石和天然铜的岩脉发育良好。角砾状黄铜矿中镍铁矿的弯曲矿脉偶尔会延伸此类矿脉。变质-热液镍铁矿脉尺寸可达200​​×10微米。附近发育直径达 12 微米的 Nielsenite metasomes。Yoko-Dovyren 镍铁矿的成分稳定且接近化学计量比，公式为 Pd1.01Cu2,81Fe0,17Ni0,01。Yoko-Dovyren Nielsenite 与 Skergaard 侵入岩的 Nielsenite 正模的不同之处在于不存在 Pt 和 Au 杂质以及明显的 Fe 杂质。Yoko-Dovyren Nielsenite 很可能出现在高逸度 О2 和极低硫化物硫逸度（在约 300°C 时 log f S2 < –24）的孕黄长石-菱镁矿变质相条件下。Yoko-Dovyren Nielsenite 与 Skergaard 侵入岩的 Nielsenite 正模的不同之处在于不存在 Pt 和 Au 杂质以及明显的 Fe 杂质。Yoko-Dovyren Nielsenite 很可能出现在高逸度 О2 和极低硫化物硫逸度（在约 300°C 时 log f S2 < –24）的孕黄长石-菱镁矿变质相条件下。Yoko-Dovyren Nielsenite 与 Skergaard 侵入岩的 Nielsenite 正模的不同之处在于不存在 Pt 和 Au 杂质以及明显的 Fe 杂质。Yoko-Dovyren Nielsenite 很可能出现在高逸度 О2 和极低硫化物硫逸度（在约 300°C 时 log f S2 < –24）的孕黄长石-菱镁矿变质相条件下。