Effect of ore dressing on flotation of copper and arsenic minerals in sulphide ore processing

Monomineral flotation results showed that the use of a new reagent S-cyanoethyl N, N-diethyldithiocarbamate enhances the flotation activity of chalcopyrite, in contrast to flotation with butyl xanthate, and reduced the flotation ability of arsenopyrite, which makes this reagent promising for its use in the selective flotation of complex sulfide ores.

Assessing potential hazard of technogenic formations of natural and man-made complexes of some sulphide deposits of the Eastern Zabaykalye

The analysis of chemical composition of technosol and soil samples from Akatuyevsky and Blagodatsky polymetallic deposit mines of the Eastern Zabaykalye revealed that the main pollutant in the soil samples is As. Material excess of the Maximum allowable concentrations was registered for Pb, Zn, Cd and Mn. Calculation of potential hazard coefficients showed that the most hazardous for the environment are man-made formations of Akatuyevsky and Blagodatsky mines. Of all the chemical elements which are most commonly encountered at the Akatuyevsky and Blagodatsky mines technosol the most hazardous are As, Pb, Zn and Cu. It is noted that these chemical elements are part of sulphide ore minerals.

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.

Prospects for the development of underground ore mining geotechnologies at the Talnakh and Oktyabrskoye deep mines

Rich sulphide, cuprous and impregnated ores are currently mined in the underground mines of the Talnakh and Oktyabrskoye deposits at the depths from 250 to 1,700 m. The reserves of rich ores are depleted, and therefore the growth of cuprous and impregnated ores is gaining importance. Their share may reach 80% of the total production by 2030. A distinctive feature of such deposits is the occurrence of cuprous and impregnated ores above the rich sulphide ore, which reserves have been mined out using mining systems with curing backfill mixtures. In this context, mining of impregnated ores will be done in the undermined zones, which will lead to significant rock mass deformation, opening of existing natural and formation of new cracks, will affect the stability of mining structures and will require special measures to control rock pressure in the mines. The paper presents the results of assessing the stress-and-strain condition of the undermined mass of impregnated ores mined using the room-and-pillar cut-and-fill method at the depths of 500, 1000 and 2000 m. The assessment shows that no dangerous stress concentrations arise in the mining structures at great depths which creates preconditions for the safe development of such deposits. A significant increase in ore extraction will require upgrading of existing underground facilities. It is proposed to carry out pre-concentration of the mined ore in the underground conditions using modern crushing complexes, high-capacity mine separators to remove waste rock, which can subsequently be used as the backfill material. In this way, a closed-loop mining system is created that meets the efficiency requirements of mining production and integrated subsoil development.

Editorial for Special Issue “Supergene Evolution of Polymetallic Deposits, Including Non-Laterite Fe and Mn Ores”

This Special Issue of Minerals published 3 years after the issues on non-sulphide ore deposits [...]

Pretreatment to Leaching for a Primary Copper Sulphide Ore in Chloride Media

The dissolution of copper sulphide ores continues to be a challenge for the copper industry. Several media and leaching alternatives have been proposed to improve the dissolution of these minerals, especially for the leaching of chalcopyrite. Among the alternatives, pretreatment prior to leaching was proposed as an option that increases the dissolution of copper from sulphide ores. In this study, a mineral sample from a copper mining company was used. The copper grade of the sample was 0.79%, and its main contributor was chalcopyrite (84%). The effect of curing time (as pretreatment) in a chloride media on copper sulphide ore was evaluated at various temperatures: 25, 50, 70 and 90 °C. The pretreated sample and leaching residues were characterized by X-ray diffraction, scanning electron microscopy, and reflected light microscopy. Pretreatment products such as CuSO4, NaFe3(SO4)2(OH)6, and S0 were identified although with difficulty, due to the low presence of chalcopyrite in the initial sample (1.99%). Under the conditions of 15 kg/t of H2SO4, 25 kg/t of NaCl, and 15 days of curing time, a copper extraction of 93.1% was obtained at 90 °C with 50 g/L of Cl− and 0.2 M of H2SO4.