The De’erni Cu–Zn-Co deposit is a typical altered ultramafic-hosted volcanogenic massive sulfide deposit comprising four lenticular main orebodies (0.57 Mt Cu, 1.27% Cu average ore grade; 0.03 Mt Co, 0.09% Co average ore grade; 0.16 Mt Zn, 1.04% Zn average ore grade) hosted in serpentinite and a 200-m-thick basalt was found below the No. I orebody. Serpentinite spinel Al₂O₃, TiO₂, Cr#, and Mg# indicate a mantle-source. Serpentinite magmatic-hydrothermal genesis is indicated by the following: (i) high Rb/Y and Th/Zr ratios, low Nb/Zr ratios, and low δ⁶⁵Cu values; (ii) altered magnetite rims on spinel being characterized by high Cr, Ni, and Ti, and low Ga contents; (iii) pyrite appears along the boundary of spinel grains and has a higher Co and Ni content than pyrite in ores. Therefore, the ultramafic host rocks are formed by strong fluid alteration of primary mantle rocks. The compositional zoning of Co, Cu, and Zn in euhedral coarse-grained pyrite from massive sulfide ore suggests that metal enrichment was associated with three fluid phases, with a clear temporal interval between the fluid activity that introduced Co/Cu enrichment and Zn enrichment (Zn-rich veins in magnetite cross-cut early spinel). Serpentinite exhibits a higher Zn content and decoupling of Ni and Co contents compared to Dur’ngoi ophiolite serpentinite distal from the orebody, implying primary ultramafic rocks may have provided Co to the ores. The apparently high Cu content of the Dur’ngoi ophiolite basalt in comparison with ophiolite basalts worldwide indicates basalt may have supplied the Cu.

德尔尼铜锌钴矿床是典型的蚀变超镁铁质火山成因块状硫化物矿床，由四个透镜状主矿体组成（0.57 Mt Cu，平均矿石品位 1.27%；0.03 Mt Co，平均矿石品位 0.09%；0.16 Mt Zn（平均矿石品位 1.04%）赋存于蛇纹岩中，在 I 号矿体下方发现了 200 米厚的玄武岩。蛇纹石尖晶石Al ₂ O ₃、TiO ₂、Cr#和Mg#表明地幔源。蛇纹岩岩浆-热液成因特征如下： (i) 高 Rb/Y 和 Th/Zr 比值、低 Nb/Zr 比值和低 δ ⁶⁵ Cu 值； (ii) 尖晶石上的蚀变磁铁矿边缘，其特征在于高 Cr、Ni 和 Ti，以及低 Ga 含量； (iii) 黄铁矿沿尖晶石晶粒边界出现，其 Co 和 Ni 含量高于矿石中的黄铁矿。因此，超镁铁质围岩是由原生地幔岩强烈的流体蚀变形成的。来自块状硫化物矿石的自形粗粒黄铁矿中 Co、Cu 和 Zn 的成分分带表明，金属富集与三个流体相相关，在引入 Co/Cu 富集和 Zn 富集的流体活动之间存在明显的时间间隔。磁铁矿中的富锌矿脉横切早期尖晶石）。与远离矿体的 Dur'ngoi 蛇绿岩蛇纹岩相比，蛇纹岩表现出更高的 Zn 含量以及 Ni 和 Co 含量的解耦，这意味着原生超镁铁岩可能向矿石提供了 Co。与世界范围内的蛇绿岩玄武岩相比，Dur'ngoi 蛇绿岩玄武岩的 Cu 含量明显较高，这表明玄武岩可能提供了 Cu。