The classification of the tetrahedrite group minerals in keeping with the current IMA-accepted nomenclature rules is discussed. Tetrahedrite isotypes are cubic, with space group symmetry I43m. The general structural formula of minerals belonging to this group can be written as M(2)A6M(1)(B4C2)X(3) D4S(1)Y12S(2)Z, where A = Cu+, Ag+, ☐ (vacancy), and (Ag6)4+ clusters; B = Cu+, and Ag+; C = Zn2+, Fe2+, Hg2+, Cd2+, Mn2+, Cu2+, Cu+, and Fe3+; D = Sb3+, As3+, Bi3+, and Te4+; Y = S2– and Se2–; and Z = S 2–, Se2–, and ☐. The occurrence of both Me+ and Me2+ cations at the M(1) site, in a 4:2 atomic ratio, is a case of valency-imposed double site-occupancy. Consequently, different combinations of B and C constituents should be regarded as separate mineral species. The tetrahedrite group is divided into five different series on the basis of the A, B, D, and Y constituents, i.e., the tetrahedrite, tennantite, freibergite, hakite, and giraudite series. The nature of the dominant C constituent (the so-called “charge-compensating constituent”) is made explicit using a hyphenated suffix between parentheses. Rozhdestvenskayaite, arsenofreibergite, and goldfieldite could be the names of three other series. Eleven minerals belonging to the tetrahedrite group are considered as valid species: argentotennantite-(Zn), argentotetrahedrite-(Fe), kenoargentotetrahedrite-(Fe), giraudite-(Zn), goldfieldite, hakite-(Hg), rozhdestvenskayaite-(Zn), tennantite-(Fe), tennantite-(Zn), tetrahedrite-(Fe), and tetrahedrite-(Zn). Furthermore, annivite is formally discredited. Minerals corresponding to different end-member compositions should be approved as new mineral species by the IMA-CNMNC following the submission of regular proposals. The nomenclature and classification system of the tetrahedrite group, approved by the IMA-CNMNC, allows the full description of the chemical variability of the tetrahedrite minerals and it is able to convey important chemical information not only to mineralogists but also to ore geologists and industry professionals.

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Concentration data are reported for 18 trace elements in chalcopyrite from a suite of 53 samples from 15 different ore deposits obtained by laser-ablation inductively-coupled plasma-mass spectrometry. Chalcopyrite is demonstrated to host a wide range of trace elements including Mn, Co, Zn, Ga, Se, Ag, Cd, In, Sn, Sb, Hg, Tl, Pb and Bi. The concentration of some of these elements can be high (hundreds to thousands of ppm) but most are typically tens to hundreds of ppm. The ability of chalcopyrite to host trace elements generally increases in the absence of other co-crystallizing sulfides. In deposits in which the sulfide assemblage recrystallized during syn-metamorphic deformation, the concentrations of Sn and Ga in chalcopyrite will generally increase in the presence of co-recrystallizing sphalerite and/or galena, suggesting that chalcopyrite is the preferred host at higher temperatures and/or pressures. Trace-element concentrations in chalcopyrite typically show little variation at the sample scale, yet there is potential for significant variation between samples from any individual deposit. The Zn:Cd ratio in chalcopyrite shows some evidence of a systematic variation across the dataset, which depends, at least in part, on temperature of crystallization. Under constant physiochemical conditions the Cd:Zn ratios in co-crystallizing chalcopyrite and sphalerite are typically approximately equal. Any distinct difference in the Cd:Zn ratios in the two minerals, and/or a non-constant Cd:Zn ratio in chalcopyrite, may be an indication of varying physiochemical conditions during crystallization.Chalcopyrite is generally a poor host for most elements considered harmful or unwanted in the smelting of Cu, suggesting it is rarely a significant contributor to the overall content of such elements in copper concentrates. The exceptions are Se and Hg which may be sufficiently enriched in chalcopyrite to exceed statutory limits and thus incur monetary penalties from a smelter.

Many minor/trace elements can substitute into the crystal lattice of galena at various concentrations. In-situ LA-ICP-MS analysis and trace element mapping are used to obtain minor/trace element data from a range of natural galena specimens aiming to enhance understanding of the governing factors that control minor/trace element partitioning. The coupled substitution Ag + + (Bi, Sb) 3+ ↔ 2Pb 2+ , is confirmed by data obtained, although when Bi and/or Sb are present at high concentrations (~> 0.002 mol.%), site vacancies most likely come into play through the additional substitution 2(Bi, Sb) 3+ + □ ↔ 3Pb 2+. Galena is the primary host of Tl in all mapped mineral assemblages. Thallium is likely incorporated into galena along with Cu through the coupled substitution: (Ag, Cu, Tl) + + (Bi, Sb) 3+ ↔ 2Pb 2+. Tin can reach significant concentrations in galena, particularly when the latter formed via metamorphic recrystallisation. Tin is concentrated in galena, likely via the substitution: Sn 4+ + □ ↔ 2Pb 2+ , involving the creation of lattice vacancies, or Sn 2+ ↔ Pb 2+. Tin and In concentrations show a strong positive correlation across the sample suite indicating that the availability of these elements is intimately linked in natural systems. Cadmium and minor Hg can be incorporated into galena; the simple isovalent substitution (Cd, Hg) 2+ ↔ Pb 2+ is inferred. Significant oscillatory compositional zoning, and lesser sector zoning of minor/trace elements (Ag, Sb, Bi, Se, Te) is confirmed, for the first time, in galena from two epithermal ores. Zoning is attributed to slow crystal growth into open spaces within the vein at relatively low temperatures. The datasets generated increase understanding of the nature and distribution of minor/trace elements in galena, and partitioning between galena and coexisting minerals. These data have several applications in the minerals industry, particularly in studies of mineral deposit genesis, ore processing and, potentially, also in mineral exploration.

Laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS) has rapidly established itself as the method of choice for generation of multi-element datasets for specific minerals, with broad applications in Earth science. Variation in absolute concentrations of different trace elements within common, widely distributed phases, such as pyrite, iron-oxides (magnetite and hematite), and key accessory minerals, such as apatite and titanite, can be particularly valuable for understanding processes of ore formation, and when trace element distributions vary systematically within a mineral system, for a vector approach in mineral exploration. LA-ICP-MS trace element data can assist in element deportment and geometallurgical studies, providing proof of which minerals host key elements of economic relevance, or elements that are deleterious to various metallurgical processes. This contribution reviews recent advances in LA-ICP-MS methodology, reference standards, the application of the method to new mineral matrices, outstanding analytical uncertainties that impact on the quality and usefulness of trace element data, and future applications of the technique. We illustrate how data interpretation is highly dependent on an adequate understanding of prevailing mineral textures, geological history, and in some cases, crystal structure.

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Minerals of the tetrahedrite isotypic series are widespread components of base metal ores, where they co-exist with common base metal sulphides (BMS) such as sphalerite, galena, and chalcopyrite. We used electron probe microanalysis and laser-ablation inductively-coupled plasma mass spectrometry to obtain quantitative multi-trace element data on tetrahedrite-tennantite in a suite of 37 samples from different deposits with the objective of understanding which trace elements can be incorporated, at what levels of concentration, and how the presence of tetrahedrite-tennantite influences patterns of trace element partitioning in base metal ores. Apart from Fe and Zn, Hg and Pb are the two most abundant divalent cations present in the analysed tetrahedrite-tennantite (up to 10.6 wt % Hg and 4 wt % Pb). Cadmium, Co and Mn are also often present at concentrations exceeding 1000 ppm. Apart from one particularly Te-rich tetrahedrite, most contained very little Te (around 1 ppm), irrespective of prevailing assemblage. Bismuth is a common minor component of tetrahedrite-tennantite (commonly > 1000 ppm). Tetrahedrite-tennantite typically hosts between 0.1 and 1000 ppm Se, while Sn concentrations are typically between 0.01 and 100 ppm. Concentrations of Ni, Ga, Mo, In, Au, and Tl are rarely, if ever, greater than 10 ppm in tetrahedrite-tennantite and measured W concentrations are consistently <1 ppm. Taking into account the trace element concentrations in co-crystallizing BMS, the results presented allow the partitioning trends between co-crystallized sphalerite, galena, chalcopyrite, and tetrahedrite-tennantite to be defined. In co-crystallizing BMS assemblages, tetrahedrite-tennantite will always be the primary host of Ag, Fe, Cu, Zn, As, and Sb, and will be the secondary host of Cd, Hg, and Bi. In contrast, tetrahedrite-tennantite is a poor host for the critical metals Ga, In, and Sn, all of which prefer to partition to co-crystallizing BMS. This study shows that tetrahedrite-tennantite is a significant carrier of a range of trace elements at concentrations measurable using contemporary instrumentation. This should be recognized when establishing protocols for trace element analysis of tetrahedrite-tennantite, and when assessing the main hosts of trace elements in any given assemblage, e.g., for geometallurgical purposes.

Three samples of (Tl,Sb,As)-rich pyrite from the ore deposits of southern Apuan Alps (Tuscany, Italy) 15were studied through a multi-technique approach in order to constrain the speciation and incorporation 16 mechanism of thallium in pyrite. High concentrations of Tl, Sb, and As were detected in all the studied 17 samples through laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS). Average 18 Tl contents were 1,299 ppm, 1,967 ppm, and 2,623 ppm in samples from Sennari, Canale della Radice, 19 and Fornovolasco, respectively. The LA-ICP-MS time-resolved down-hole ablation profiles were 20 smooth indicating that Tl, Sb, and As are dissolved in the pyrite matrix, or occur in homogeneously 21 distributed nanoparticles (NPs). X-ray absorption spectroscopy (XAS) data revealed that Tl, Sb, and As 22 occurs as Tl + , Sb 3+ , As 3+ , and As 1-. In all the studied samples, bond distances and coordination numbers 23 for Sb 3+ and As 3+ are constant, whereas Tl displays a range of coordination numbers (~3 to ~6),