Copper Ore Research Articles

Assessing the Economic Value of Copper Mineral Resources in Ta Phoi Area, Lao Cai Province

Copper ore is one of the minerals that play an important role in the economic development of Lao Cai province. However, this is a non-renewable resource with high risk and great environmental impact in the mining process. Therefore, it is necessary to study and evaluate the economic value of mineral resources, creating a basis for planning the process of exploration, exploitation, rational use of resources, and environmental protection. This paper evaluates the economic value of mineral resources using resource assessment techniques. The total reserves and identified resources are 21,473 thousand tons of ore, corresponding to 160,278 tons of copper. In the case of using level 122 reserves, the identified resources is 16,412 thousand tons of ore, corresponding to 129,433 tons of copper. The forecasted resources are approximately 41,050 thousand tons of ore, which is equivalent to 198,235 tons of copper. The accompanying minerals, with a resource level 333, include 6.34 tons of gold (Au) and 24.39 tons of silver (Ag). The results show that copper content in the area is varied from 0.01% to 9.18% with an average of 1.50%, and the ore grade is changed from poor to medium. The distribution of copper ores is relatively uniform to very uneven, with the largest concentration found in the Ta Phoi area. The calculated potential recovery value (GTNth) and unit area value (URV) of copper minerals in the study area are substantial, with the highest URV is observed in the Ta Phoi area and the lowest one is obtained in the Coc San area. During the extraction process, the investor should consider recovering accompanying elements such as gold and silver to enhance the mine's economic value.

Study on Process Mineralogy of the Combined Copper Oxide Ore in Tibet and Acid Leaching Behavior with Calcium Fluoride

The Yulong copper deposit in Tibet is a typical porphyry copper deposit, with about 30 million tons of copper oxide ore in the surface layer. However, more than 40% of the copper resources are in a combination state, resulting in an extraction efficiency of only 50% for copper via the hydrometallurgical process. In this study, the process mineralogy of the combined copper oxide ore was systematically investigated and a calcium fluoride-enhanced leaching process is proposed to increase the leaching efficiency of the combined copper ore. The process mineralogy of the combined copper oxide ore was analyzed using various testing techniques, including chemical analysis, X-ray diffraction, and a process mineralogy parameter testing system (Mineral Liberation Analysis). The results revealed that limonite accounted for 86.12% of the sample, and 63.51% of the copper resource existed in the form of combined copper oxide in limonite. However, it is difficult for the uniformly distributed combined copper oxide in limonite to sufficiently make contact with sulfuric acid, which is the leaching agent, resulting in low copper leaching efficiency. The enhanced leaching behavior of the combined copper oxide ores was also investigated, thereby determining effective and economical enhanced leaching conditions. Under optimal conditions, at a grinding fineness ratio of −0.074 mm (accounting for 85%), liquid-solid ratio of 4:1, sulfuric acid concentration of 50 g/L, temperature of 30 °C, CaF2 dosage of 1% of the ore mass, and leaching time of 4 h, the copper leaching efficiency increased to 60.57%, which was 7.34% higher than that of atmospheric pressure leaching. Finally, the enhanced leaching slag was analyzed using an electron probe microanalyzer. It indicated that fluorine ions can erode the combined copper oxide ore and facilitate the diffusion of hydrogen ions inside the limonite, thereby achieving a strengthening effect.

Corrosion Resistance of Scraped Copper in Velocity Varied Inland Water of Bangladesh

Copper (Cu) is widely used for electrical wires, equipment parts, and components in commercial, industrial, and marine fields due to its excellent electromechanical properties. With rapid scientific and technological advancement and economic development, the demand for copper is increasing continuously. As such, scraped items have become important to meet the rising demand considering the depletion level of copper ores in nature. But sometimes old copper contains tin (Sn), lead (Pb), etc., which may alter its properties. Thus, it is necessary to characterize different properties, including corrosion resistance, to explore the appropriate engineering applications of scraped copper waste items. In this context, the present research reports the study of the corrosion behavior of pure Cu and scraped Cu in the river water environment of Bangladesh for the submersed period of 36 days. The investigations have been carried out for three relative velocity conditions of fluid, i.e., 0, 2 and 4 m/s. A gravimetric analysis was done to find out the corrosion rate. The results of this study indicate that the presence of only 1%Sn and 1%Pb in copper has significantly increased the corrosion rate in all three velocity conditions. At the same time, scraped copper's average corrosion rate has been increased by about 10% while the relative velocity is changed from 0 to 4 m/s. Micrographs have confirmed the extent of corrosion severity resulting from chemical composition and fluid velocity alterations.

Out of the Fiery Crucible: Egyptian Old Kingdom metallurgy

The evidence for Egyptian Old Kingdom metalworking is reviewed drawing upon archaeology, iconography, metallurgy, history, scientific data and process replication. The charateristics of arsenical copper is considered concluding that Old Kingdom copper ore was initially obtained from the southern Eastern Desert of Egypt where Pre- and Early Dynastic mines are to be found and where there may have been mining and metallurgical expertise amongst the regional nomadic people or further south in Africa. Chaîne opératoires are proposed for the fabrication of prestige copper vessels and for the production copper tools.

Effect of Iron Ore and Copper Ore Tailings on Engineering Properties and Hydration Products of Sustainable Cement Mortar

Abstract The prohibition of river sand mining has drawn the attention of researchers in finding practicable alternatives. In the approach of finding these alternatives, it is essential to ensure minimal or zero impairment to the ecological balance, which can be mainly attained by making use of industrial waste/byproducts. The wastes from the mining industry are the major contributors in causing impairment to the environment, and their influence on the stability of mortars on using as fine aggregates needs to be systematically investigated with the view of long-term performance concerns. Thus, the present study explores the applicability of mine tailings and finding the optimum dosage in cement mortars by investigating the engineering properties and microstructure development with the aid of qualitative and quantitative analysis associated with hydration products. The studies confirm that the increased consumption of portlandite for secondary hydration reactions followed by the additional formation of calcium silicate hydrate (CSH) and calcium aluminum silicate hydrate (CASH) phases in mine tailing-based mortars helped in achieving a quality microstructure. These additional formations of CSH and CASH phases are also confirmed through Fourier transform infrared spectroscopy by identifying the shift of Si-O-Si stretching vibration bands toward a lower wavenumber. The lowering of calcium/silicate atomic ratio and increased formation of mineralogical compounds related to CSH and CASH in x-ray diffraction patterns also confirms the same. Gismondine, chabazite, and hillebrandite are the additional phases formed and found to take part in refining the pore structure. This enhanced performance of mine tailing mortars was also verified with the aid of a modified Andreasen and Andersen particle packing model. The formation of high-quality microstructure is reflected in the hardened properties of optimized cement mortar in the proportion of 20 % for iron ore tailing and 30 % for copper ore tailing.

Analysis of the Possibilities of Energy Recovery from Gravity Flows in Pipelines in a Copper Ore Enrichment Plant

Considering the need to reduce climate change and energy costs, the possibilities of energy recovery have been sought for many years, even if this should involve significant complexity of the technological process. Attempts to recover energy from a flowing medium containing a large amount of a solid phase are rather rare. This is mainly due to unfavorable erosion and sludge phenomena. The aim of this work is to analyze the possibility of recovering energy from gravity flows in the pipelines of a copper ore enrichment plant. The analysis will be carried out for a system operating in a plant in Poland. An energy recovery device will be designed taking into account the flow of a two-phase medium. For this purpose, flow calculations will be performed. The calculation results obtained for the two-phase flow will be verified based on the experimental results presented in the literature. The simulations will make it possible to determine the power of the designed device.

Геолого-географическая экспедиция А.А. Кейзерлинга и П.И. Крузенштерна на Европейский Северо-Восток России

The paper provides information about the expedition to the European North of Russia in 1843. The expedition travelled about 8000 miles (about 8427 km). The main route was connected with the wa-terway along the rivers Vychegda, Pechora, Izhma and their tributaries. Hiking routes were connected with the description of the Ural Mountains sites (Bolvano—Iz, Skala). On reindeer sledges, the expedition reached the coast of the Barents Sea and carried out geological and geographical work in the Timan tundra. The work was supervised by a paleontologist, corresponding member of the St. Petersburg Academy of Sciences, Count A.A. Keyserling. The scientist described and paleontologically characterized the rocks of the Lower Silurian, Devonian, Permian, Jurassic and Lower Cretaceous age. As a result of the expedition, the main minerals (coal, gypsum, oil, domanic, copper ore, salt, grindstone) were studied. The significant geological and geographical result was the discovery of the Timan Ridge and its mapping. P.I. Krusenstern conducted topographic surveys, astronomical and geographical observations. He compiled a geographical map on a scale of 1:3000000 with a rectangular geographic grid and detailed drawing of rivers, lakes and settlements. The published works of the scientists are kept in the funds of the A. A. Chernov Geological Museum, Institute of Geology.

A bulk sorting trial of copper ore using a magnetic resonance analyser

Sensor-based bulk ore sorting (BOS) is a technique that may lead to uplift of processing grades by excluding waste as well as an increase in usable resource by sorting material designated as mineralised waste. A magnetic resonance analyser (MRA) was installed on the primary crushed ore feed to the sulphide plant at the Kansanshi copper mine in northwestern Zambia to trial BOS. The conveyor belt operated at 2800tph and carried ore of which greater than 85% by weight of the copper-bearing minerals are chalcopyrite. The MRA was therefore tuned for chalcopyrite’s zero static field magnetic resonance. The analyser achieved a 3σ detection limit of 0.045 wt% copper as chalcopyrite over a 4 s measurement time and standard belt loading, with lower detection thresholds possible if the measurement time increased.A trial of ore diversion was then carried out at the site. Pods of ore measured as less than 0.2 wt% copper as chalcopyrite by the MRA were diverted by a dead box diverter system to form a low-grade stockpile of approximately 10,000 tonnes. A cavity in the mill feed stockpile was arranged and the rejected material fed back through the crusher, past the MRA and directly through the milling circuit to the flotation feed where a Vezin sampler was used to take a sample every 5 min. This sample was then tested for copper grade by the site metallurgical laboratory. The MRA measured a grade of 0.16 wt% copper as chalcopyrite over the test time period and the Vezin samples for the last hour of the trial reported approximately 0.2–0.3 wt% copper despite some mixing with unsorted ore being inevitable. This is as clear a demonstration of bulk ore sorting (BOS) as practically achieveable in the production environment at Kansanshi and, to the author’s knowledge, the first demonstration of BOS on a copper ore stream of at least this throughput.

Corrosion behavior of high- and low-chromium steel grinding balls in chloride solution

The corrosion behaviour of three types of alloys (two low-alloy carbon steel and one stainless iron with ~15 wt.% Cr), in a solution which simulates seawater (3% NaCl solution, pH 8.1) was tested. Tested samples are used to make steel (iron) balls applied in mils for grinding copper and other ore. The corrosion tests were performed using three electrochemical methods, at room temperature in the presence of atmospheric oxygen. The linear polarization resistance (LPR) method, electrochemical impedance spectroscopy (EIS) method, and linear sweep voltammetry (LSV) method were applied. Based on measurements by LPR and EIS methods (as non-destructive methods), the value of polarization resistance (Rp) was determined and the general corrosion rate (vcorr) of the examined samples was calculated. The obtained values of the general corrosion rate can be used to calculate the service life of steel (iron) balls under exploitation conditions (seawater). The appearance of the surface after linear sweep voltammetry (LSV) measurement showed the presence of localized corrosion (pits were formed) of the tested samples, especially stainless iron, and the LSV method is not suitable for the determination of the general corrosion rate of tested samples in seawater. This form of corrosion occurs at high anodic polarizations, during performing LSV measurements.

Non-ferrous metal of the Bronze Age of Northern Kazakhstan: geochemical characteristics and ore base

The chemical composition of 29 copper and bronze artifacts from the sites of the Petrovka and Alakul Cultures located be-tween the Tobol and Ishim Rivers (the burial grounds of Bekteniz and Dzhangildy 5, and the sites of Novonikolskoye 1 and Semioz-ernoye 2; Northern Kazakhstan) were analysed using mass spectrometry with inductively coupled plasma and laser ablation. The sites are 14C dated to the interval between the 19th–17th centuries BC. In the examined sample, the leading metallurgical group with a slight prevalence in both Petrovka and Alakul metals was “pure” copper; the second part of the metal was represented by tin bronzes — low-alloyed (up to 8 wt.% Sn) in the Petrovka, and high-alloyed (Sn up to 21 wt.%) in the Alakul Culture. The statistical analysis of the main components of trace elements in the metal demonstrated a division into six main geochemical groups. Among these, tin bronzes with an uninterpretable copper component (10 specimens), “pure” copper of Ural origin with Fe-Co-Ni-As-Zn correlations (9 specimens), and “pure” copper with polymetallic Sn-Pb-As-Ag-Se specialization (10 copies), corresponding to the ores of copper deposits of the Kokshetau anticlinorium, can be identified. An overview of the tectonic structures of Northern Ka-zakhstan shows the nearby presence of several porphyry copper and skarn deposits with ancient mines (Imantau, Baksinskoye, Akkan-Burlukskoye, etc.), which likely served as sources of copper ore. Closely associated with these are Greisen and quartz-vein-greisen tin deposits, but there is no reliable information about their use in ancient times. According to the composition of tin alloys in the analysed metal, two main types can be distinguished: tin (without correlation with other impurity elements) when using pure cassiterite, and tin-lead (with increased concentrations and correlation of As, Au, Bi, etc.) when using cassiterite-sulfide ores. The data show the association of the Bronze Age sites of Northern Kazakhstan with the ore and raw materials base in this region, and the intensity of trade exchange of metallurgical products between the Ural and Kazakhstan centers of metal production.

A novel magnetic geopolymer-based adsorbent prepared from heated glauconite and separated magnetite: Experiments and statistical physics treatment for crystal violet

Sinai copper ore with 9.48 % of Fe2O3 was treated using a laboratory-scale mineral processing techniques that included size reduction (below 75 µm) and a wet low intensity drum-type magnetic separation. After this treatment method, the separated magnetite product containing about 85 % of Fe2O3 was extracted. A mixture of heated glauconite (900 °C/2h) and the extracted magnetite was activated by sodium silicate (Na2SiO3) to obtain a novel glauconite-based magnetic geopolymer (namely GMG). Several analytical techniques (i.e., XRD, XRF, FESEM, FTIR, EDX, TEM, elemental mapping, and zeta potential) were used in the characterization of GMG and its performance for crystal violet (CRV) remediation was studied. The equilibrium data at pH 8.0 and 25 – 50 °C were fitted to a statistical physics multilayer model and classical isotherm equations to understand the CRV adsorption mechanism. The theoretical calculations indicated that GMG can adsorb 1.12 to 1.39 of CRV molecules per functional group (n), suggesting the presence of a multi-interaction mechanism and vertical adsorption orientation on GMG surface. For this basic dye, the estimated saturation adsorption capacities (Qsat) ranged from 684 to 612 mg/g, and an exothermic binding interaction was associated with the removal of this dye molecule. The adsorption energies (ΔE) ranged between 15.05 and 36.74 kJ/mol, indicating that physical forces, such as electrostatic interactions and hydrogen bonds, governed the GMG-CRV interactions. After fourth adsorption–desorption cycles, the regenerated GMG showed 74 % of its adsorption capacities, which suggested the suitability of this adsorbent to be regenerated and reused multiple times in water treatment. Overall, the combination between the separated magnetite and glauconite was an effective approach for the remediation of effluents that contain dye molecules

Enhanced leaching of copper from refractory oxidized copper ore by calcium fluoride: Behavior and mechanism

The Luanshya area of Zambia is rich in copper oxide resources. However, copper mainly exists in biotite and phlogopite, which presents challenges for efficient extraction. To improve the leaching rate of copper from these ores, local hydrometallurgical plants use heating and stirring; however, the leaching rate is not high. To address the issue in this work, CaF2 was introduced as a leaching aid, and the effects of various parameters on leaching were systematically studied. The results revealed that when the dosage of CaF2 is 5wt% of raw ore mass, the dosage of sulfuric acid is 120 kg/t, the leaching temperature is 60 °C, and the leaching time is 200 min with a slurry concentration of 30wt%, the leaching rate of copper can reach 80.44%. Compared with regular heating stirring acid leaching, the copper leaching rate was found to increase by 8.76%, while the leaching temperature decreased by 5 °C and the leaching time shortened by 40 min. The results of the HSC Chemistry 6.0 thermodynamic calculations and mechanism analysis indicated that F can promote the fracture of Si–O and Al–O bonds in the crystal structure of biotite and phlogopite in sulfuric acid solution, enabling a direct reaction between the acid and copper. The proposed method can be applied not only to the treatment of cupriferous mica ores but also to the processing of other copper ores. This process is more efficient and cost-effective than the regular heating–stirring acid leaching process.

Geomechanical and Technical Aspects of Torpedo Blasting under Seismic and Rockburst Hazard Conditions in Legnica–Glogow Copper District Mines

The dominant hazard in the Polish copper ore mining industry (LGCD mines—Legnica–Glogow Copper District) is the occurrence of mining tremors and rockbursts. One of the effective active methods of preventing this threat is torpedo blasting, which results in disturbing the structure of roof rocks. A change in the integrity of a roof, especially in the tremor-generating layer or in the contact between stiff rock layers, reduces the possibility of an elastic energy concentration and may also be a kind of stress concentrator, provoking the destruction of rocks. This article presents original solutions for determining the areas of rock mass within a mining area where it is advisable to conduct torpedo blasting, and the experience of blasting in the Rudna copper mine in the LGCD is described. The first part of this article presents the results and experiences of using torpedo blasting prevention in the LGCD mine conditions in the Rudna mine. Assuming that due to the stress of the rocks, torpedo blasting brings the greatest benefits in the areas of elastic energy concentration, the second part of this article presents the results of numerical modeling, on the basis of which the zones of elastic energy concentration in the form of total, shear and volume deformation were determined in the vicinity of mining activities for typical geological and mining conditions in the LGCD. The importance of methods for the verification of the proposed solutions based on the analysis of seismic activity and geophysical mechanisms of events’ foci and seismo-acoustic emissions was also emphasized. The numerical simulations performed and conclusions from in situ observations allowed the formulation of general principles for the selection of torpedo blasting parameters.

Visual inspection results and evaluation of Akhtala tailing safety based on tailing management facility safety methodology

Relevance. Mining sector is one of the leading branches of the industry in Armenia. Therefore, effective government regulation of the sector based on a sound legal basis is a necessity. Accidents at tailing management facilities are posing a high risk to people and environment especially in their near vicinity and often have a transboundary impact. The tailing management facility safety methodology elaborated under the auspices of the German Environmental Agency is an efficient tool for quick assessment of the technical condition of the tailing management facilities. Aim. To present the results of application of the tailing management facility methodology in Armenia, which was applied to the operated Nahatak tailing management facility of the Akhtala Ore Dressing Combine (Lori region, Armenia). Objects. Tailing management facility methodology was applied to the operated tailing management facility Nahatak of the Akhtala Ore Dressing Combine, for which all documentation was checked. Enrichment wastes were stored at the tailing management facility during processing copper ore from the Shamlug mine and polymetals from the Akhtala mine. The main visual inspection was carried out in three parts of the tailing management facility: main dam, drainage canal and secondary dam. Special attention was drawn to main dam conditions. The video recorded by a drone was used to explore the dam bottom-line. Methods. The tailing management facility methodology includes the following elements: the method of evaluation of Tailings Hazard Index; the tailing management facility checklists including the questionnaire for visual and documentation inspection, the evaluation matrix for the tailing management facility safety level; the measures catalogue for taking actions to improve tailing management facility safety. The questions of the each tailing management facility checklist are stated in a way to encompass the minimum set of the requirements, critical for tailing management facility safety, which allows evaluating the tailing management facility conditions. Questions in all groups of the checklist are sorted by the tailing management facility lifecycle and each subsection contains relevant questions applied to a specific stage (design, construction, operation, re-cultivation, closure). Application of the tailing management facility checklist is supported by a measures catalogue with short-, medium- and long-term safety measures. Results. The tailing management facility methodology was used/tested for the operated tailing management facility in Armenia for the first time. Тhe main problems of the Nahatak tailing management facility were identified and analyzed, and appropriate recommendations were provided based on them. Based on the obtained results it can be concluded that the main problems are related to the drainage system and the management of water flows, some parts of the primary dam that require restoration, as well as the improvement of monitoring systems. At the same time the experience of application of the tailing management facility methodology in Armenia, allowed improving this methodology and making it the most effective working tool for quick and efficient visual inspection of tailing management facilities and for thorough inspection of relevant documentations. The user-friendly tailing management facility safety methodology (with questionnaires of visual and documentation checking) is an efficient tool for quick assessment of the technical condition of the tailing management facilities, as well as for training staff both in the governance bodies and in mining enterprises.

Geogas prospecting for igneous ore deposits covered by regolith: the Zijinshan high-sulfidation epithermal Cu–Au deposit in the Cathaysia Block

The mining industry faces a challenge due to the scarcity of outcrop or near-surface mineral deposits, necessitating the development of low-cost and efficient prospecting methods to explore through cover. Inductively coupled plasma mass spectrometry has been applied to geological sample analysis, and scientists have gradually improved the method of geogas prospecting. As a result, geogas prospecting has shown promising results in detecting underlying concealed Au, U and Cu–Ni deposits covered by Gobi sand and Quaternary sediments. To verify the effectiveness of this method for exploring underlying concealed mineral deposits developed in igneous covered areas, the Zijinshan high-sulfidation epithermal Cu–Au deposit, a concealed mineral deposit in southeastern China, was selected as the experimental field. Our experiments revealed nanoscale particles composed of Au, Cu–Fe and Cu–other elements in the geogas captured above the ore bodies of the deposit. Furthermore, Cu–nanoscale particles retain the isotopic composition of copper found in both the oxidation zone and deep copper ores. The geogas samples exhibited similar C1-chondrite normalized REE distributions, with REE patterns indicating significant enrichment of LREE relative to HREE and similar (La)N/(Sm)N and (Gd)N/(Yb)N ratios. These characteristics are similar to those of the gold ores, copper ores, altered rock and bedrock near the ore bodies. These findings suggest that deep-penetration geochemical methods using geogas can be a valuable tool for uncovering underlying concealed mineral deposits in igneous covered areas.

Inexpensive composite copper ore/red mud oxygen carrier: Industrial granulation via hydroforming and multiple-cycle evaluation in chemical looping combustion

The industrial granulation of low-cost and high-performance oxygen carriers (OCs) is critical to developing MW or larger-scale chemical looping combustion (CLC) demonstration units. In this work, an inexpensive composite OC, Cu10.9Red89.1@C (8.72 wt% copper ore and 71.28 wt% red mud bonded by 20 wt% cement), is innovatively prepared at a large scale by the hydroforming method. Its long-period performance is comprehensively evaluated in a thermogravimetric analyzer (TGA) and a batch fluidized bed, and TGA results show that Cu10.9Red89.1@C exhibits excellent stability and reactivity even in the case of deep reduction by H2 in TGA. In addition, an obvious activation of Cu10.9Red89.1@C is observed during the CH4 CLC test, indicated by the increased CH4 conversion and CO2 selectivity from 81.58 % and 74.65 % in the 1st cycle to 97.53 % and 98.24 % after activation, respectively. With Cu20Fe80@C (16 wt% copper ore and 64 wt% iron ore bonded by 20 wt% cement) as a reference, Cu10.9Red89.1@C presents a higher CH4 conversion, CO2 selectivity, and faster oxygen transfer rate due to its larger specific surface area and alkali metals in it. Finally, the cost analysis concludes that its production cost is only $0.95/kg for Cu10.9Red89.1@C, much cheaper than other large-scale prepared OCs. This work provides theoretical support for the applicability of the hydroforming method and the oxygen carrier Cu10.9Red89.1@C.

A review on 3D printable cementitious material containing copper and iron ore tailings: material characterization, activation methods, engineering properties, durability, and microstructure behavior

A review on 3D printable cementitious material containing copper and iron ore tailings: material characterization, activation methods, engineering properties, durability, and microstructure behavior

Assessment of Concrete Hollow Blocks Incorporating Polyethylene Terephthalate (PRT) and Copper Slag as a Commercial Concrete Alternative

The increasing demand for durable and sustainable concrete driven by population growth and urbanization, highlights the need for an environmentally friendly alternative to traditional concrete, by innovating and recycling the top waste made by industries, given the country’s vulnerability to natural disasters and the environmental impact of concrete production. Polyethylene Terephthalate (PET) waste accounts for up to 13.9% of all waste plastics, posing a serious hazard to the environment and ecology both on land and in oceans (Ye et al., 2023); similarly, copper slag, a by-product of the smelting and processing of copper ore, is generated at a rate of 2.2 tons per ton of copper produced, leading to an annual figure of 24.6 million tons of slag (Gabasiane et al., 2021). With this, researchers are still finding ways to search for an alternative to lessen the environmental waste whilst contributing to the construction industry. Subsequently, this study aims to test the viability and effectiveness of Polyethylene Terephthalate and Copper Slag-induced concrete hollow blocks as an alternative to traditional commercial concrete hollow blocks. The researchers used a Post-Test Only Controlled Group Design, providing a complete understanding of their effect on concrete performance. By utilizing purposive sampling, the researchers were able to select shredded PET as their chosen samples. The raw data from the test results of varying ratios were treated using ANOVA. In terms of compressive strength and water absorption percentage, the 30-70 ratio emerged as the most durable, while in density, the commercial concrete displayed the highest amount. Upon comparative analysis, the results from the data treatment shows a significant difference in incorporating Polyethylene Terephthalate and Copper slag into concrete, specifically the 30% PET and Copper slag to 70% cement ratio, therefore rejecting the null hypothesis. It is advised to explore more ratios to accommodate different construction demands and have a minimum curing time of 28 days before testing the qualities of the said concrete hollow blocks.

Lead isotopes of prehistoric copper tools define metallurgical phases in Late Neolithic and Eneolithic Italy.

The diffuse presence of small copper ore deposits in the Alpine area, mostly exploited since Late Medieval times, led most scholars to assume that these deposits may actually be active much earlier and that many of the circulating prehistoric metal objects found in the area were produced with local copper sources. This assumption was recently validated for the Recent Bronze Age through the use of lead isotope tracers, and well supported by the archaeometallurgical evidences found in the South-Eastern Alps. However, the scarcity of available lead isotope data for pre-Bronze Age metals precluded to date the reconstruction of the metal flow through the Late Neolithic and Eneolithic (or Copper Age). Based on 49 new analyses of important archaeological objects from the Alpine region, the Po River Valley and Central Italy, mostly axes dated from the Late Neolithic to the Late Eneolithic, here we show that the diffusion of copper in Northern Italy (approximately 4500-2200 BC) includes three major periods of metal use and/or production, each related to specific ore sources. The South Alpine copper was massively used only starting from the middle of the 3rd millennium BC, in connection or slightly earlier than the Beaker event.

An Analysis of the Impact of Mining Excavation Velocity on the Development of Gaseous and Gaseous Geodynamic Hazards in Copper Ore Mines

The hazards of gaseous geodynamic phenomena and rockbursts are among the most challenging to assess and classify. This perception arises from both a review of the literature and an examination of available instructions and regulations in underground mining facilities. The hazard of gaseous geodynamic phenomena in Polish copper ore mines only appeared in 2009, whereas these phenomena occur and are commonly described in other mining countries. In Polish copper ore mines, due to the room and pillar system in fields with lengths of about 460 m, very often parallel to neighboring fields, which together give a length of about 900 m, it is difficult to identify the location of gas traps due to the large size of the area. This paper presents an analysis of the influence of the velocity of the excavation on the possibility of escalating or reducing the described mining hazards. An analysis of the impact of excavation velocity on the state of gaseous geodynamic and roof fall hazards was conducted for two mining fields. For the considered mining fields, the hypothesis was formulated that an excavation velocity greater than or equal to 17 m/month positively influences a reduction in both gaseous geodynamic and roof fall hazards.