Search results for "Sphalerite"
showing 9 items of 9 documents
The influence of natural trace element distribution on the mobility of radionuclides. The exemple of nickel in a clay-rock
2015
International audience; The natural distribution of nickel (Ni) in the Callovian–Oxfordian clay-rich rock of Bure (France) was investigated, together with that of cobalt (Co), zinc (Zn) and lead (Pb). The most Ni-enriched phases are pyrite (∼400 × 10−6 g g−1 Ni), sphalerite (∼300 × 10−6 g g−1), chlorite (∼285 × 10−6 g g−1), organic matter (∼300 × 10−6 g g−1), muscovite (100–200 × 10−6 g g−1) and possibly carbonate minerals (mainly calcite and minor dolomite, ∼10 × 10−6 g g−1). Despite their high abundance (up to ∼80% in the upper part of the formation), carbonate minerals are quantitatively a minor Ni reservoir; most of the Ni is borne by chlorite and pyrite, which are minor mineral phases.…
Distribution of trace elements in willemite from the Belgium non-sulphide deposits
2019
Samples of willemite (Zn2SiO4) mineralization from the historical non-sulphide Zn–Pb deposits of La Calamine (eastern Belgium) have been recovered from collections of the Geological Survey of Belgium. Textural and chemical analyses are used to evaluate the critical element distribution (Ge, In, Ga) and deportment. willemite occurs as a variety of types that continuously formed between the protore stage (sulphides) and the late supergene stage (carbonates and hydrated phases). Different types of willemite may be distinguished on the basis of their shape and zoning characteristics, supporting a polyphase non-sulphide mineralization after the protore stage. This is also marked by a significant…
Sulfide mineral identification using laser-induced plasma spectroscopy
2003
Sulfide minerals in rock samples were identified with laser-induced plasma spectroscopy (LIPS) in the near vacuum ultraviolet spectral region. Reference spectra of pyrite, pyrrhotite, chalcopyrite, sphalerite, barite, calcite and dolomite were applied to classification of minerals in sulfur-bearing drill core samples. On the basis of the results mineral distributions in the sample were estimated. The potential of the LIPS method for in situ analysis is discussed.
Development of a Matrix-Matched Sphalerite Reference Material (MUL-ZnS-1) for Calibration of In Situ Trace Element Measurements by Laser Ablation-Ind…
2016
Sphalerite (ZnS) is an abundant ore mineral and an important carrier of elements such as Ge, Ga and In used in high-technology applications. In situ measurements of trace elements in natural sphalerite samples using LA-ICP-MS are hampered by a lack of homogenous matrix-matched sulfide reference materials available for calibration. The preparation of the MUL-ZnS1 calibration material containing the trace elements V, Cr, Mn, Co, Ni, Cu, Ga, Ge, As, Se, Mo, Ag, Cd, In, Sn, Sb, Tl and Pb besides Zn, Fe and S is reported. Commercially available ZnS, FeS, CdS products were used as the major components, whereas the trace elements were added by doping with single-element ICP-MS standard solutions a…
Vertical Distribution and Speciation of Trace Metals in Weathering Flotation Residues of a Zinc/Lead Sulfide Mine
2007
Sulfide-bearing mine tailings are a serious environmental problem around the world. In this study, the vertical distribution and speciation of Zn and Pb in the fine-grained flotation residues of a former sulfide ore mine in Germany were investigated to assess the inorganic weathering processes that effect the environmental risk arising from this site. Total metal contents were determined by X-ray fluorescence spectroscopy (XRF). Mobilizable fractions of Zn, Pb, Fe, and Mn were quantified by sequential chemical extractions (SCE). Furthermore, the speciation of Zn was analyzed by Zn K-edge extended X-ray absorption fine structure spectroscopy (EXAFS) to identify the residual Zn species. The v…
Imaging connected porosity of crystalline rock by contrast agent-aided X-ray microtomography and scanning electron microscopy
2017
We set out to study connected porosity of crystalline rock using X-ray microtomography and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) with caesium chloride as a contrast agent. Caesium is an important radionuclide regarding the final deposition of nuclear waste and also forms dense phases that can be readily distinguished by X-ray microtomography and SEM-EDS. Six samples from two sites, Olkiluoto (Finland) and Grimsel (Switzerland), where transport properties of crystalline rock are being studied in situ, were investigated using X-ray microtomography and SEM-EDS. The samples were imaged with X-ray microtomography, immersed in a saturated caesium chlorid…
High-Pressure Synthesis of Novel Boron Oxynitride B6N4O3 with Sphalerite Type Structure
2015
A novel crystalline boron oxynitride (BON) phase has been synthesized under static pressures exceeding 15 GPa and temperatures above 1900 °C, from molar mixtures of B2O3 and h-BN. The structure and composition of the synthesized product were studied using high-resolution transmission electron microscopy, electron diffraction, automated diffraction tomography, energy dispersive X-ray spectroscopy and electron energy-loss spectroscopy (EELS). BON shows a hexagonal cell (R3m, Z = 3) with lattice parameters a = 2.55(5) A and c = 6.37(13) A, and a crystal structure closely related to the cubic sphalerite type. The EELS quantification yielded 42 at % B, 35 at % N, and 23 at % O (B:N:O ≈ 6:4:3). E…
Metals and metalloids in hair samples of children living near the abandoned mine sites of Sulcis-Inglesiente (Sardinia, Italy)
2014
International audience; The Sulcis-Iglesiente district (SW Sardinia, Italy) is one of the oldest and most important polymetallic mining areas in Italy. Large outcrops of sulfide and oxide ores, as well as the products of the long-lasting mining activity, are present throughout the district releasing significant quantities of metals and metalloids into the surrounding environment. Here are reported concentrations of 21 elements determined in scalp hair samples from children (aged 11-13 years) living in different geochemical environments of southwestern Sardinia: Iglesias, hosting several abandoned mines, and the island of Sant׳Antioco, not affected by significant base metal mineralization ev…
Sulfide ore facies, fluid inclusion and sulfur isotope characteristics of the Tappehsorkh Zn-Pb ( ± Ag-Ba) deposit, South Esfahan, Iran
2020
International audience; The stratiform, stratabound Tappehsorkh Zn-Pb (± Ag-Ba) deposit, located in the southeastern part of the Malayer-Esfahan Metallogenic Belt of Iran, formed during Lower Cretaceous back-arc extension. Sulfide mi-neralization occurs within dolostone, black siltstone, and crystal lithic tuff and andesite associated with the Gushfil-Baghabrisham synsedimentary normal fault. Three sulfide ore facies (massive, bedded, and stockwork) occur in the deposit. Sulfide minerals are sphalerite, galena, tetrahedrite and pyrite with minor chalcopyrite and bornite, and gangue minerals are barite, dolomite and quartz. Sulfide mineralization textures are massive, replacement , vein-vein…