Black Sand Research Articles

The history of mining and mineral exploration in Panama: From Pre-Columbian gold mining to modern copper mining

The history of mining and exploration in Panama is a case study of the evolution of mining in a tropical, island arc environment in the New World from prehistoric to modern times over a period of ~1900 years. Panama has a strong mineral endowment of gold (~984 t), and copper (~32 Mt) resulting in a rich mining heritage. The mining history can be divided into five periods. The first was the pre-Columbian period of gold mining from near the start of the Current Era at ~100 CE to 1501, following the introduced of gold metalwork fully fledged from Colombia. Mining of gold took place from placer and vein deposits in the Veraguas, Coclé, Northern Darien and Darien goldfields, together with copper for alloying. Panama was the first country on the mainland of the Americas to be mined by Europeans during the Spanish colonial period from 1501-1821. The pattern of gold rushes, conquest and settlement can be mapped from Spanish records, starting in Northern Darien then moving west to Panama in 1519 and Nata in 1522. From here, expeditions set out throughout Veraguas over the next century to the Veraguas (Concepción), Southern Veraguas, Coclé and Central Veraguas goldfields. Attention returned to Darien in ~1665 and led to the discovery of the Espíritu Santo de Cana gold mine, the most important gold mine to that date in the Americas. The third period was the Republican period following independence from Spain in 1821 to become part of the Gran Colombia alliance, and the formation of the Republic of Panama in 1903. This period up to ~1942 was characterized by mining of gold veins and placers, and manganese mining from 1871. Gold mining ceased during World War Two. The fourth period was the era of porphyry copper discoveries and systematic, regional geochemical exploration programs from 1956 to 1982, carried out mainly by the United Nations and the Panamanian government, as well as private enterprise. This resulted in the discovery of the giant porphyry copper deposits at Cerro Colorado (1957) and Petaquilla (Cobre Panama, 1968), as well as several other porphyry deposits, epithermal gold deposits and bauxite deposits. The exploration techniques for the discovery of copper were stream sediment and soil sampling, followed rapidly by drilling. The only mine developed in this period was marine black sands for iron ore (1971-1972). The fifth and current period is the exploration and development of modern gold and copper mines since 1985 by national and foreign companies, which started in response to the gold price rise. The main discovery methods for gold, which was not analyzed in the stream sediment surveys, were lithogeochemistry of alteration zones and reexamination of old mines. Gold mines were developed at Remance (1990-1998), Santa Rosa (1995-1999 with restart planned in 2020) and Molejon (2009-2014), and the Cobre Panama copper deposit started production in 2019. The level of exploration in the country is still immature and there is high potential for the discovery of new deposits.

Black sand deposits; their spatial distribution and hazards along the northern coast of Sinai Peninsula, Egypt

Airborne Gamma Ray Spectrometric (AGRS) surveys and image processing techniques are utilized to define the occurrence of black sand deposits along Sinai's northern coastal plain. High contents of radioactive minerals are detected in these deposits; zones of high concentrations of uranium 238U, thorium 232Th, and potassium 40K could be outlined. Remote sensing and GIS techniques are integrated to study the pattern of coastline changes and its relationship to the distribution of black sand deposits during the period between 2000 and 2020. The results reveal high 232Th anomalies along El-Arish Beach due to its high monazite content; containing 7.92% ThO2. In addition, high uranium anomalies on the eastern sides of El-Bardawil Lake result from the abundance of zircon in the sediments surrounding the lake, which contain 5.29% U3O8. Areas of high radiation levels, which exceed the allowed limits for human exposure, are outlined by calculating adsorbed and annual effective dose rates. Unfortunately, many of these areas are open and easily accessible to the public, presenting a direct threat to the health of local inhabitants. These anomalous areas ought to be excluded from the ongoing national housing and land reclamation projects, where long-term exposure to high gamma radiation increases the cancer risk factor in humans.

Photocatalytic hydrogen production using FeTiO3 concentrates modified by high energy ball milling and the presence of Mg precursors

Ilmenite (FeTiO3) concentrates were modified by high energy ball milling (HEBM) at different times (1, 2, and 3 h) and in the presence of MgO or metallic Mg at different contents (0.5, 1.0, and 3.0 wt%), with the aim of obtaining a low-cost and highly available photocatalyst with enhanced performance towards H2 production. FeTiO3 concentrates were obtained from ilmenite-rich black sand by gravimetric concentration followed by wet electromagnetic and dry magnetic separation. HEBM was performed to insert Mg into FeTiO3 structure and to simultaneously reduce the particle size. The insertion of Mg intended to shift the conduction band of the materials to more negative potentials, in spite of the band-gap widening. XRD patterns of the milled samples showed a decrease in the intensity of ilmenite peaks without any displacement, indicating slight amorphization without significant changes in the crystalline structure. However, the increase in the intensity of hematite peaks suggests substitutional doping according to the proposed solid-state reactions. Although thermodynamic analyses showed that doping with metallic Mg should be more favorable, doping with MgO appears to be kinetically favored due to the physical characteristics of the precursor, as it was revealed by XRD, XPS, Raman spectroscopy, SEM–EDS, and UV–Vis DRS results. Deconvolution of high-resolution XPS spectra corresponding to Mg1s exhibited the presence of an additional component peak for the sample milled with metallic Mg, in comparison to that with MgO. This result evidenced the formation of a new phase, suggesting that part of the metallic Mg was not inserted into FeTiO3, as it was confirmed by Raman spectroscopy. UV–Vis DRS analyses showed an increase in the band-gap of the samples milled in the presence of Mg precursors (from 2.51 to 2.55–2.59 eV) which were attributed to slight modifications of the conduction band due to the insertion of Mg. The performance towards hydrogen production under UV irradiation was improved from 240.5 µmol g−1 h−1 (unmilled sample) to 255.3 µmol g−1 h−1 (2 h milled in the absence of Mg precursor), 296.0 µmol g−1 h−1 (2 h milled with 1.0 wt% MgO), and 265.2 µmol g−1 h−1 (2 h milled with 1.0 wt% metallic Mg). This improvement was attributed mainly to the insertion of Mg, and the consequent modification of the band structure, rather than the modification in the surface area.

Provenance of late Republican Roman pottery from Caput Adriae revealed by non-invasive mineral chemistry of melanitic garnets and other igneous minerals

Quite rare pottery shards showing a paste rich in black sand particles, possibly igneous minerals, have been discovered in late Republican Roman sites of Trieste area (NE Italy) and SW Slovenia in the Caput Adriae. Most of them belong to late Greco-Italic and Dressel 1 amphora types, in use from the end of the 3 rd and the beginning of 1 st centuries BC. Following a methodological procedure based on the analysis of igneous temper, proved to be particularly effective by several scholars, numerous minerals have been extracted from the surface of 16 pottery shards, without causing any visible damage to them. Microprobe analysis has allowed the identification of igneous minerals (olivine, clinopyroxene, feldspar and garnet), most likely originating from the Roman or Campanian magmatic provinces. The chemistry of garnets, indicated in the past as a possible tracer of ancient commerce but no longer used in the last decades to study Italian late Republican pottery, has proved to be a promising tool to distinguish among the two magmatic provinces. According to our study, most of the investigated garnets-bearing samples would originate from Somma-Vesuvius while some of them from Latium.

Geospatial analysis of the source of monazite deposits and the dynamics of natural radionuclides in the selected coastal environs of Kerala, south west coast of India

Present study is an attempt to identify the source of monazite deposits and understand the dynamics of natural radionuclides in the coastal environs of Alappuzha and Thiruvananthapuram districts, south west coast of India. The source of monaztite bearing black sands was identified by combining the activity concentration of the natural radionuclides, lithology and drainage systems of Alappuzha and Thiruvananthapuram districts. The activity concentrations of naturally occurring radionuclides (40K, 226Ra, and 232Th) in sand samples collected from the study area were determined using high efficiency NaI(Tl) detector. The radiological parameters viz. radium equivalent activity (Raeq), absorbed dose rate (D), annual effective dose (indoor and outdoor), annual gonadal dose equivalent, and excess lifetime cancer risk were also determined from the activity concentration and compared with the values reported for the other regions of the world. The results of these systematic investigations are presented and discussed in detail in the manuscript.

Wisata Berbasis Masyarakat dalam Meningkatkan Kebersihan dan Perekonomian Masyarakat di Desa Pengastulan - Bali

Pengastulan Beach is a coast located in the north of the island of Gods, precisely in the Kauman Hamlet, Pengastulan Village, Seririt subdistrict, Buleleng Regency, Bali. In the past, this beach was the same as most beaches in general which were only used as a place to make a living for fishermen. But over time, due to the lack of garbage disposal facilities in Pengastulan Village and many factories dumping their waste to Pengastulan beach, the beach becomes sullied and neglected. The current research uses qualitative research methods. The data was collected through interviews, observation, and documentation. The purpose of this study are to determine the components and facilities of coastal tourism in Pengastulan, to determine community empowerment on the coast of Pengastulan, and to determine the supporting and inhibiting factors of the community empowerment Pengastulan coast. The results of this study show that: 1) The components of Pengastulan beach as a tourist attraction are parking lots, food stalls, boat rentals, cafes, mosques, restrooms, rest areas and many others. 2) Community empowerment is carried out by giving the community full rights to manage their souvenir shops, boat rentals and even to become tour guides. 3) The internal supporting factor comes from the availability of natural resources, such as beach panoramas with sunsets, black sand beaches with sea waves, rich underwater life, and the friendliness of the people. As for the external supporting factors, there are economic growth, increased interest in traveling, cultural diversity and advances in information and technology. The inhibiting factors are resource and preference barriers.

Manufacturing and Mechanical Characterization of Fly-Ash-Reinforced Materials for Furnace Lining Applications

Fly ash is the major wastes generated during the combustion of coal in thermal power plants. More than 110 million tons of fly ash produced in India annually. It leads to a significant disposal problem. An attempt has been made by numerous researchers to integrate the fly ash in the industry sector. The key applications include the manufacturing of bricks, production of cement, soil amelioration, mine backfilling, etc. Nevertheless, the refractory bricks for furnace lining are mainly formed from iron and steel, which are imported and are very expensive. Hence, to tackle this issue, the current study is focused on the synthesis of fly-ash-rich brick for high-temperature applications. In this investigation, fly ash material combined with minor additives such as granite powder, alite cement, and black sand were manufactured. The pellets of these materials with a varying additive percentage from 5 to 30% were prepared using hydraulic pressure. The heat-treated pellets were physically and mechanically characterized to ensure the brick properties suitable for furnace lining applications. Surface morphology of raw materials and particle–particle interaction after palletization were evaluated using scanning electron microscopy. Energy Dispersive x-Ray Analysis and x-ray diffraction technique were conducted to detect elemental analysis and phase evaluation of raw materials and fly-ash-rich brick after heat treatment. Microhardness of the samples was determined using a Vickers hardness tester. It is found that the formation of various complex compounds with respect to constituent composition, and pellet formation temperature has a great influence on the variation in hardness.

Instrumental neutron activation analysis of lanthanides and coexisting elements in monazite samples and group separation using synthesized inorganic ion exchangers

Abstract Samples of Egyptian monazite ore obtained from black sand of Abu-Khashaba, Rashied (Rosetta) area on the Mediterranean Sea coast were analyzed for some lanthanides and coexisting elements using instrumental neutron activation analysis (INAA). The analyses were carried out qualitatively and quantitatively for the elements Ce, Nd, Eu, Gd, Tb, Yb and Sc, La as well as the accompanying elements Co, Cr, Fe, Hf, Nb, Zn, Zr in addition to the actinides Th and U; whereas after relatively longer decay time the following lanthanide elements were analyzed: Ce, Nd, Eu, Gd, Tb, Yb and Sc, beside the accompanying elements Co, Cr, Fe, Hf, Nb, Zn, Zr and Th. Two certified reference materials (CRM) were used in this study. For sorption studies, radioactive isotopes 141Ce, 160Tb, 169Yb, 95Zr, 181Hf, and 95Nb were prepared by neutron irradiation to trace the adsorption behaviors of their corresponding elements under certain conditions. Furthermore, radiochemical separation of the analyzed elements in the irradiated monazite samples in sulfuric acid solutions was carried out. Ion exchange technique was applied under static and dynamic conditions and the employed inorganic ion exchangers were locally synthesized and characterized using FT-IR and scanning electron microscopy (SEM) tools. Good group separation of the analyzed lanthanide elements from the accompanying elements was achieved.

Data on phase and chemical compositions of black sands from "El Ostional" beach situated in Mompiche, Ecuador.

Data revealing the phase and chemical compositions of natural black sands from “El Ostional” beach, located in the northern Ecuadorian Pacific coast have been presented. The samples were collected from six points over the shore area of approximately 500 × 40 m2. The data on crystalline phases (iron titanium oxide, orthoclase feldspar and zircon) were determined by X-ray powder diffraction (XRPD), while semi-quantitative chemical analyses of major (Fe and Ti) and trace elements were obtained by X-ray fluorescence spectroscopy (XRF). The phase composition was verified by scanning electron microscopy (SEM), using backscattered electron (BSE) mode and energy dispersive spectroscopy (EDS). These comprehensive data are a contribution to valorize ilmenite-hematite solid solutions from natural resources towards the identification of novel technological applications.

Productivity enhancement of traditional solar still by using sandbags of El Oued, Algeria

AbstractThis manuscript aims to study the experimental analysis of solar still with sandbags as energy storage materials. To achieve this idea, 25 bags filled with El Oued sand was fixed inside a square basin vertically and distributed regularly, this is called the modified solar still with sandbags (MSS‐SB). The sand used in this study is very effective than many store mediums considered within many previous works such as glass balls, sponges, phosphate, yellow sand, black sand, and black gravel. This fact is due to its components characterized by high thermal conductivity. By using the Fourier‐transform infrared spectroscopy, X‐ray diffraction, and X‐ray fluorescence, it has been confirmed that the chemical properties of El Oued sand are composed mainly by 97.6% quartz (SiO2) and 0.56% calcite (CaCO3) and very low concentrations of some other oxides. To obtain the influences of the sandbags utilized in this study, the performance of MSS‐SB and traditional solar still (TSS) was tested at the same climatic conditions of the southeast of Algeria throughout 24 hours. Experimental results revealed that the overall cumulative distillate yield of TSS reached 3.76 L/m2/d, while for utilization the sandbags for MSS‐SB increase the cumulative distillate yield to 5.06 L/m2/d, representing 34.57% improvement in cumulative distillate yield. Also, the daily efficiency of TSS 33.1%, while for utilization the sandbags for MSS‐SB increases the daily efficiency to 44.63%, representing 34.83% improvement in daily efficiency.

Correlation between radon release, radioactivity and mineralogy: a case study of Estonian black sands

The growing attention to naturally occurring radionuclides in building materials has a significant societal impact. This impact is apparent in recent research studies and the latest European Council directives, where reference levels for indoor radon concentrations and gamma radiation levels are reported. This paper studies black sand samples from the Estonian coast, mainly from Kihnu island. The results are discussed from various aspects to determine if utilization of these sands as a building material component is viable. For this reason, this paper focuses on the mineralogical and radiological characterization of these samples with special attention to radon emanation and exhalation. Furthermore, a detailed correlation study of mineralogical components against emanation and exhalation factors and the levels of 226Ra, 232Th and 40K was performed. It is found that the sand samples are composed of very high heavy mineral content as compared to the rest of Estonia; the black sands studied here include a heavy fraction dominated by garnets and a light fraction characterized by quartz and feldspars. The analysis also indicates that the higher 232Th and 226Ra content in the samples is correlated with an increase in zircon, ore minerals and garnets; on the other hand, the 40K content is connected to amphiboles. A strong correlation was also found between the 226Ra activity concentration and the measured massic exhalation rates.

Copper-rich “Halo” off Lake Superior’s Keweenaw Peninsula and how Mass Mill tailings dispersed onto tribal lands

Over a century ago, shoreline copper mills sluiced more than 64 million metric tonnes of tailings into Lake Superior, creating a “halo” around the Keweenaw Peninsula with a buried copper peak. Here we examine how tailings from one of the smaller mills (Mass Mill, 1902–1919) spread as a dual pulse across southern Keweenaw Bay and onto tribal L’Anse Indian Reservation lands. The fine (“slime clay”) fraction dispersed early and widely, whereas the coarse fraction (stamp sands) moved more slowly southward as a black sand beach deposit, leaving scattered residual patches. Beach stamp sands followed the path of sand eroding from Jacobsville Sandstone bluffs, mixing with natural sands and eventually adding onto Sand Point, at the mouth of L’Anse Bay. Dated sediment cores and a multi-elemental analysis of the buried Cu-rich peak in L’Anse Bay confirm a tailings origin. Copper concentrations are declining in the bay, yet copper fluxes remain elevated. The spatial and temporal studies underscore that enhanced sediment and copper fluxes around the Keweenaw Peninsula largely reflect historic mining releases. Mercury is correlated with copper, yet mercury concentrations and fluxes remain relatively low in Keweenaw Bay compared to nearby Superfund sites (Torch and Portage Lakes), perhaps reflecting the absence of smelters on Keweenaw Bay. Tribal efforts to remediate contamination are progressing, but are hindered by recent high water levels plus severe storms. The long-term repercussions of Mass Mill discharges caution against mine companies discharging even small amounts of tailings into coastal environments.

Radioactivity and Risk Assessment with Uncertainty Treatment for Analysis of Black Sand Minerals

Precise radiological analysis of environmental, ores, nuclear materials and minerals samples is of great value for monitoring and surveillance objectives. The information deduced from the analysis can be used to identify the origin and nature of the accompanied activities. This work focuses on analysis of some black sand ore samples to identify and quantify their radioisotopes and potential risk. The analysis can provide useful information about the environmental transport mechanism and about the sources of radionuclides in the studied area; Rashid city coast, Egypt. To achieve this target, a Non‐destructive gamma spectrometer (NDGS) was used to trace and amount the radioisotopes types and activities. The efficiency was calculated with uncertainty treatment. The specific activity with uncertainty assessment of 238U, 232Th decay series and 40K of these samples were varied from 72.2 to 252.4 with average value 111 ± 25 Bq·kg–1, 94.2 to 579.8 with average value 140 ± 22 Bq·kg–1 and 427.9 to 527.5 with average value 475 ± 36 Bq·kg–1 respectively. The mineralogical signature of the analyzed samples (XRD) indicates that the samples are mainly composed of ilmenite, zircon, rutile, sphene and monazite. The potential risk assay shows that the hazard parameters of these samples; the Absorbed Gamma Dose Rate (AGDR), Gamma Activity Index (Iγ), Annual Effective Dose Rate Equivalent (AEDRE), Radium equivalent, External and Internal Hazard Index (Hex and Hin) are of specific characteristics. The total absorbed gamma dose rate and the annual effective dose due these samples were found to be with average values 158 ± 24 (nGy/h) and 195 ± 29 (μSv/y) which are higher than the world average value of 59 nGy/h and 70 μSv/y respectively. The results obtained are important to establish baseline levels to detect any upcoming changes due to any activities. It can be observed that the studied area has elevated thorium and uranium content. The relatively high dose rate will be considered as a spa for the physical therapy such as treatment of some skin diseases and rheumatoid.

Beachgoing Butterflies: Marine Puddling on Black Sand Beaches of Tangkoko Batuangus Nature Reserve, North Sulawesi

Beachgoing Butterflies: Marine Puddling on Black Sand Beaches of Tangkoko Batuangus Nature Reserve, North Sulawesi

Shoreline Evolution along a Placer Mining Beach of South-West Coast of India

Prasad, R.; Sheela Nair, L.; Kurian, N.P., and Prakash, T.N., 2020. Shoreline evolution along a placer mining beach of south-west coast of India. In: Sheela Nair, L.; Prakash, T.N.; Padmalal, D., and Kumar Seelam, J. (eds.), Oceanic and Coastal Processes of the Indian Seas. Journal of Coastal Research, Special Issue No. 89, pp. 150-157. Coconut Creek (Florida), ISSN 0749-0208.The Chavara coast of 22 km length located along the south-west coast of India is well known for its rich heavy mineral deposits, also called as black sand deposits. Since 1930, the Indian Rare Earths Ltd. (IREL) and its predecessor companies have been engaged in beach sand mining along this coast for the extraction of heavy minerals. The mining of beach sand by the IREL and Kerala Minerals and Metals Ltd. (KMML) has been much beyond the sustainable limits for the past one and a half decades as indicated by different studies, and has caused drastic beach and innershelf morphological changes. In this study numerical modelling is carried out using the LITLINE module of LITPACK to simulate the shoreline evolution along this coast. The model outputs are calibrated and validated using the shorelines derived from satellite imageries and field measurements for the years 2000, 2006, 2010 and 2015. The calibrated and validated model has been used for further simulations for the period of 2000–2022 by inserting groins in tally with the field scenarios for different years. The influence of the short and long groins is predominant at the northern end, near to the Kayamkulam breakwater. If the present scenario persists, the deposition at the southern breakwater at Kayamkulam will be stabilized by the year of 2022. Orientation of the shoreline in the groin field area is found to be in accordance with the predominant northerly longshore transport. Due to the impact of intense mining, the recession in the shoreline and caving-in at the mining site will be even up to 300 m during the period of 2000–2022. The simulations show that the observed caving-in at the mining sites will aggravate further in the years to come if unsustainable mining is continued.

Fort-Dauphin beach sands, south Madagascar: natural radionuclides and mineralogical studies

The Fort-Dauphin beach sand placer occurs as black sands on the East-South of Madagascar. The placer contributes 2/3 of the total heavy mineral resources of this country. The major minerals of the deposit are monazite, zircon, quartz, garnet, spinel, sillimanite as non-refractory minerals; ilmenite, anatase, rutile, titanite, leucoxene, pseudorutile and as a refractory one. The average concentration of the ilmenite, monazite, zircon and other minerals is 66.72%, 2.3%, 2.8%, and 28.18% respectively. Ilmenite contains 63 wt.% of TiO2, Zircon - 44 wt.% of ZrO2, Monazite contains 53 wt.% of oxide rare earth elements (REE) and up to 2 wt.% of UO2 and 9 wt.% of ThO2. The total REE in the studied samples was observed high concentration up to 16000ppm and a high ratio of Σ LREE/Σ HREE>31. The principal natural radionuclide in this placer is 232Th with the concentration of 232Th from 2710 to 6000 ppm, 3620 ppm on average while for the 238U from 124 to 340 ppm, 237 ppm on average which are higher than the average of their in Earth’s crust 360 and 70 times respectively.

Fort-Dauphin beach sands, south Madagascar: natural radionuclides and mineralogical studies

The Fort-Dauphin beach sand placer occurs as black sands on the East-South of Madagascar. The placer contributes 2/3 of the total heavy mineral resources of this country. The major minerals of the deposit are monazite, zircon, quartz, garnet, spinel, sillimanite as non-refractory minerals; ilmenite, anatase, rutile, titanite, leucoxene, pseudorutile and as a refractory one. The average concentration of the ilmenite, monazite, zircon and other minerals is 66.72%, 2.3%, 2.8%, and 28.18% respectively. Ilmenite contains 63 wt.% of TiO2, Zircon - 44 wt.% of ZrO2, Monazite contains 53 wt.% of oxide rare earth elements (REE) and up to 2 wt.% of UO2 and 9 wt.% of ThO2. The total REE in the studied samples was observed high concentration up to 16000ppm and a high ratio of Σ LREE/Σ HREE>31. The principal natural radionuclide in this placer is 232Th with the concentration of 232Th from 2710 to 6000 ppm, 3620 ppm on average while for the 238U from 124 to 340 ppm, 237 ppm on average which are higher than the average of their in Earth’s crust 360 and 70 times respectively.

Happy Beach Coastal Landscape Design, Based on Landscape Engineering Adjustment

Coastal Landscape design based on landscape engineering adjustment is a coastal landscape design which applying theory, mathematical and physical modelling to practical design problems. The objective of this research is to analyze the characteristic of site and to design coastal landscape based on landscape engineering adjustment, in addition to make a sustainable site landscape design. Happy beach is one of unexposed black sand beach to many tourists, which has beautiful and clean ocean scenery. Dolphin watching tour is the main potential nature attraction to the site through riding boat at every sunrise. Methods that used in this research in design process; 1. Project acceptance; 2. Research analysis, by exploring some potential, amenity, obstacle and danger signal of site; 3. Design, the creative process of responding to condition while concentrating meaning; 4. Construction drawing. Landscape engineering approach was used to solve some specific site problem such us stormwater, climate, and beach sand which deadly for plants. The rainfall intensity value of 101.72 mm / hour. The amount of runoff is 13 m3/s it has a relatively small value. From the temperature data of Tukadmungga Village for one year, which is listed in Table 1, it can be concluded that the highest temperature reaches 31 °C. The highest temperature occurs in September 2018 to March 2019. In the range of November to April, the position of the sun against the site can be illustrated with sun path diagram. By knowing the position of the sun, we can determine the exact position of vegetation planting, which is located in the west and east of the building. m3/s0.13 m3/s Happy Beach Landscape Design include the detail of material properties which has the best performance for its using, climate, and design concept. Coastal landscape design eventually will be a recommendation for Tukadmungga village perbekel office and also North Bali Ministry of public work.

Assessment of inhaled dust by workers and suspended dust for pollution control change and ergonomic intervention in metal casting industry: A cross-sectional study

Metal casting industry including is an industry which produce high dust pollution (fly ash). Improvements in the form of ergonomic interventions have been carried out by many companies, but do not guarantee all parameters run well. The total indoor suspended dust (TSP) measurement results are not enough to guarantee healthy working conditions. Additional assessment of workers' inhaled dust is needed to change pollution control and work improvement to ergonomics. The design of this study is Cross Sectional Study. Research subjects numbered 84 people. All samples met the inclusion criteria. Measurement results of Characteristic of research subject, Working Environment Conditions, Exposition of dust inhaled by workers, Total Indoor Suspended Dust of the Company (p > 0.05). Found critical hours of workers exposed to dust (fly ash), starting from 4 h after working (Department of Process Cement, Department of Black Sand) and 2 h after working for the Department of Loam. Critical hours exposed to dust (fly ash) used as the basis for company management and regulators to take new policies in controlling fly ash pollution and ergonomic interventions. Ergonomic interventions can be carried out by activating the dust collector at critical hours, applying active resting hours at critical hours and conditioning workers to breathe fresh air. The impact of this ergonomic intervention is a decrease in musculoskeletal complaints by 25.27%, reduction in boredom 25.01%, and an increase in job satisfaction 38.46%.

Effect of Mineralogy on the Beneficiation of REE from Heavy Mineral Sands: The Case of Nea Peramos, Kavala, Northern Greece

Beneficiation of a rare earth element (REE) ore from heavy mineral (HM) sands by particle size classification in conjunction with high-intensity magnetic separation (HIMS) was investigated. The HM sands of Nea Peramos, Kavala, Northern Greece, contain high concentrations of REE accommodated mainly in silicate minerals, such as allanite. However, the potential of the Northern Greek placer for REE exploitation has not been fully evaluated due to limited on-shore and off-shore exploration drilling data. Characterization of the magnetic separation fractions using XRD and bulk ICP-MS chemical analysis showed that the magnetic products at high intensities were strongly enriched in the light REE (LREE), relative to the non-magnetic fraction. Allanite and titanite are the major host mineral for REE in the magnetic products but mainly allanite controls the REE budget due its high concentration in LREE. SEM/EDS and ICP-MS analysis of the different particle size fractions showed LREE enrichment in the fractions −0.425 + 0.212 mm, and a maximum enrichment in the −0.425 + 0.300 mm. The maximum enrichment is achieved after magnetic separation of the particle size fractions. Mass balance calculations showed that the maximum REE recovery is achieved after magnetic separation of each particle size fraction separately, i.e., 92 wt.% La, 91 wt.% Ce, and 87 wt.% Nd. This new information can contribute to the optimization of beneficiation process to be applied for REE recovery from HM black sands.