The Innokenty Lopatin and Friedrich Schmidt 1866 Yenissei (‘Turukhansk’) expedition: the first evidence of discovery of Norilsk-Talnakh Cu-Ni-PGE deposits

The history of the the discovery of world’s largest Ni-Cu-PGM deposits of Norilsk-Talnakh is revised. The 1866 prospecting and geographic expedition of Innokenty Lopatin and Friedrich Schmidt, studied the lowest Yenissei territories, and collected information and mineralogical samples (chalcopyrite from ‘copper slates’) proving by this the presence of a copper ore deposit in the Norilsk mountains. The deposit was developed by at least two adits since 1865 and was managed by brothers Pyotr and Cyprian Sotnikov from the settlement of Dudino (now Dudinka). This information was documented in the diaries by I. Lopatin and was reported by F. Schmidt in transactions of the Saint Petersburg Academy of Sciences. After the ‘re-discovery’ of the deposit in the 20th century the followers have ignored, omitted and incorrectly cited the information published by Friedrich Schmidt in 1869 and 1872, as well as its republishing made by Vladimir Obrutchev in 1917. The real sequence of events resulting in the discovery of Norilsk deposits has to be rewritten. In memoriam of Sergey Gorbunov (1952–2021), archaeologist, traveler, Sakhalin history specialist

Genesis and structure of the iron ore deposit of the Cape Iron Horn

Статья посвящена железорудному месторождению, представляющему собой пласт оолитовых (бурожелезняковых) руд железа, который выходит на дневную поверхность на мысе Железный Рог на берегу Таманского полуострова. Мыс имеет протяженность 1,3 км с запада на восток и высоту 55 м над уровнем моря. Склон мыса разбит многочисленными трещинами из-за эрозионного воздействия ветра и морской воды, по которым происходит откалывание оползневых тел. Актуальность работы. Железорудное месторождение на мысе Железный Рог Таманского полуострова известно с конца 19 века, в настоящее время (с 1984 года) ему присвоен статус памятника природы, из-за чего добыча сырья запрещена на всей охраняемой территории, составляющей 19 га. Однако минералогия, палеонтология и особенности геологии данного месторождения изучены недостаточно. Таким образом, представленная статья призвана в какой-то степени восполнить этот пробел. Целью проведенных исследований является выявление особенностей геологического строения, минерагении и генезиса железорудного месторождения на мысе Железный Рог Таманского полуострова. Методы работы. Основу работы составляют образцы, отобранные авторами во время полевых работ на мысе Железный Рог с июня по июль 2021 года. При выполнении работы были описаны 15 образцов, а также идентифицированы палеонтологические находки и определен их примерный возраст. Результаты работ. Установлено, что бурые железняки залегают в толще серых глин железнорогской свиты (N1-2žr) и совпадают с ними по возрасту, что подтверждается палеонтологическими находками. В разрезе были найдены только те минералы, в состав которых входит железо: борнит, вивианит, лимонит, халькопирит. В работе проанализированы структурно-текстурные особенности пласта и вмещающих его пород, а также ассоциации найденных минералов, на основании чего сделаны выводы, что данный пласт железных руд относится к хемогенному осадочному типу месторождений, образованному из коллоидных растворов The article is devoted to an iron ore deposit, which is a layer of oolitic (brown limestone) iron ores, which comes to the surface during the day at Cape Iron Horn on the shore of the Taman Peninsula. The cape has a length of 1.3 km from west to east and a height of 55 m above sea level. The slope of the cape is broken by numerous cracks due to the erosive effects of wind and sea water, along which landslide bodies are chipping away. Relevance.The iron ore deposit at Cape Iron Horn of the Taman Peninsula has been known since the end of the 19th century, currently (since 1984) it has been given the status of a natural monument, which is why the extraction of raw materials is prohibited in the entire protected area of 19 hectares. However, mineralogy, paleontology and features of the geology of this deposit have not been studied enough. Thus, the presented article is intended to fill this gap to some extent. The Aim of the research is to identify the features of the geological structure, mineralogy and genesis of the iron ore deposit at Cape Iron Horn of the Taman Peninsula. Methods. The work is based on samples selected by the authors during field work at Cape Iron Horn from June to July 2021. During the work, 15 samples were described, as well as paleontological finds were identified and their approximate age was determined. Results.It has been established that brown ironstones lie in the thickness of gray clays of the Zheleznogorskaya formation (N1-2žr) and coincide with them in age, which is confirmed by paleontological findings. Only those minerals containing iron were found in the section: bornite, vivianite, limonite, chalcopyrite. The paper analyzes the structural and textural features of the formation and its host rocks, as well as the associations of the minerals found, on the basis of which it is concluded that this iron ore formation belongs to the chemogenic sedimentary type of deposits formed from colloidal solutions

Multi-Scale X-Ray Computed Tomography Analysis to Aid Automated Mineralogy in Ore Geology Research

Ore characterization is crucial for efficient and profitable production of mineral products from an ore deposit. Analysis is typically performed at various scales (meter to microns) in a sequential fashion, where sample volume is reduced with increasing spatial resolution due to the increasing costs and run times of analysis. Thus, at higher resolution, sampling and data quality become increasingly important to represent the entire ore deposit. In particular, trace metal mineral characterization requires high-resolution analysis, due to the typical very fine grain sizes (sub-millimeter) of trace metal minerals. Automated Mineralogy (AM) is a key technique in the mining industry to quantify process-relevant mineral parameters in ore samples. Yet the limitation to two-dimensional analysis of flat sample surfaces constrains the sampling volume, introduces an undesired stereological error, and makes spatial interpretation of textures and structures difficult. X-ray computed tomography (XCT) allows three-dimensional imaging of rock samples based on the x-ray linear attenuation of the constituting minerals. Minerals are visually differentiated though not chemically classified. In this study, decimeter to millimeter large ore samples were analyzed at resolutions from 45 to 1 μm by AM and XCT to investigate the potential of multi-scale correlative analysis between the two techniques. Mineralization styles of Au, Bi-minerals, scheelite, and molybdenite were studied. Results show that AM can aid segmentation (mineralogical classification) of the XCT data, and vice versa, that XCT can guide (sub-)sampling (e.g., for heavy trace minerals) for AM analysis and provide three-dimensional context to the two-dimensional quantitative AM data. XCT is particularly strong for multi-scale analysis, increasingly higher resolution scans of progressively smaller volumes (e.g., by mini-coring), while preserving spatial reference between (sub-)samples. However, results also reveal challenges and limitations with the segmentation of the XCT data and the data integration of AM and XCT, particularly for quantitative analysis, due to their different functionalities. In this study, no stereological error could be quantified as no proper grain separation of the segmented XCT data was performed. Yet, some well-separated grains exhibit a potential stereological effect. Overall, the integration of AM with XCT improves the output of both techniques and thereby ore characterization in general.

Colusite from the Plavitsa gold deposit – a new mineral for the Republic of North Macedonia Gotse Zlatkov

The Plavitsa ore deposit is a part of the Zletovo ore field. Two ore zones were established: primary (sulphide) and secondary (oxide, gold-bearing). The colusite occurs at the primary sulphide ore zone. The results of the microprobe analyses in wt%: Cu 47.38, V 3.41, Sn 8.28, As 10.75, Sb 2.01, Fe 0.11, S 29.1. LA-ICP-MS revealed contents of Te, Se, In, Ag, and Au. The micro-hardness (H) is 280–310 kg/mm2. At λ 540 and 580 nm R is 29% and 29.6%. The colusitе associates with enargite, famatinite, luzonite, bornite, barite, tennantite, tetrahedrite and tellurides of Au and Ag.

Factor analysis of the geochemical associations in the Plavica ore deposit, Republic of North Macedonia

The aim of this study is to investigate the geochemical associations in the Plavica deposit in Republic of North Macedonia. The analyses of drill core samples from the detail exploration works were statistically processed to determine the groups of chemical elements with common spatial distributions. The resulting geochemical groups represent different stages of the ore forming hydrothermal processes. The main ore elements are represented by geochemical association of ([As, Sb, Au, Sn] Cu, Bi, Fe, Ag) which group outlines the ore bodies.

Geochemical and Mineralogical Characteristics of Garnierite From the Morowali Ni-Laterite Deposit in Sulawesi, Indonesia

The Morowali Ni-laterite deposit is located in the East Sulawesi Ophiolite, which is a large ophiolite belt on Sulawesi Island, Indonesia. The Morowali deposit is developed on a laterite profile due to ophiolite weathering, with saprolite, limonite, and ferruginous cap horizons from the bottom to top. Based on the occurrence of garnierite as the main ore, occurring in the saprolite horizon, it can be classified that the ore deposit is hydrous Mg silicate-type. The Ni ore is classified into different types based on color and XRD and electron probe micro-analyzer analyses. Whole-rock geochemical study was also conducted to understand the mineralization process. The Morowali Ni deposit consists of serpentine-like and talc-like phases. The serpentine-like phase consists of Ni-lizardite and karpinskite (0.76–38.26 wt% NiO) while the talc-like phase is mainly composed of kerolite (4.02–8.02 wt% NiO). The serpentine-like garnierite exhibits high Ni and Fe contents and occurrence similar to that of the serpentine observed in the saprolite horizon, suggesting the serpentine-like garnierite originated from the bedrock, and Mg-Ni cation exchange occurred during laterization. Contrastingly, the lower Fe content of the talc-like phase (0.01–0.05 wt%) than the serpentine-like phase (0.14–7.03 wt%) indicates that the talc-like garnierite is of secondary origin since Fe is immobile during weathering. The Morowali Ni-laterite deposit was mainly formed during laterization. The repetition of dry and wet cycles in each year results in the formation of secondary garnierite.