Demantoid from Balochistan, Pakistan: Gemmological and Mineralogical Characterization

Acid mine drainage (AMD) occurs naturally in abandoned coal mines, and it contains hazardous toxic elements in varying concentrations. In the present research, AMD samples collected from an abandoned mine were treated with fly ash samples from four thermal power plants in Singrauli Coalfield in the proximate area, at optimized concentrations. The AMD samples were analyzed for physicochemical parameters and metal content before and after fly ash treatment. Morphological, geochemical and mineralogical characterization of the fly ash was performed using SEM, XRF and XRD. This laboratory-scale investigation indicated that fly ash had appreciable neutralization potential, increasing AMD pH and decreasing elemental and sulfate concentrations. Therefore, fly ash may be effectively used for AMD neutralization, and its suitability for the management of coalfield AMD pits should be assessed further.

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The Physico-Chemical and Mineralogical Characterization of Mg-Rich Synthetic Gypsum Produced in a Rare Earth Refining Plant

Sustainability ◽

10.3390/su13094840 ◽

2021 ◽

Vol 13 (9) ◽

pp. 4840

Author(s):

Fatai Arolu Ayanda ◽

Mohd Firdaus Mohd Anuar ◽

Syaharudin Zaibon ◽

Shamshuddin Jusop

Keyword(s):

Rare Earth ◽

Acid Soils ◽

Acid Neutralization ◽

Mineralogical Characterization ◽

X Ray ◽

Neutralization Capacity ◽

Acid Neutralization Capacity ◽

Refining Plant ◽

Calcium Magnesium

The physical, chemical and mineralogical characterization of the constituents of magnesium-rich synthetic gypsum produced in a rare earth-refining plant located in Gebeng, Pahang, Malaysia was conducted through elemental chemical analysis, scanning electron microscopy with Energy Dispersive X-ray (EDX)-analyzer, thermal analysis, X-ray fluorescence and X-ray diffraction. The crystalline nature of the by-product was studied using FTIR spectroscopy. Elemental analysis confirmed the presence of Ca and Mg, which are essential macronutrients required by plants and this Ca alongside the high pH (9.17) of MRSG may confer on the material a high acid neutralization capacity. From the result, it was observed that the studied by-product is a heterogeneous crystalline material comprising of gypsum (CaSO4.2H2O) and other major components such as calcium (magnesium) compounds (hydroxide, oxide, silicates, and carbonate) and sulfur. These aggregates may contribute to give an acid neutralization capacity to MRSG. The XRD study of MRSG indicated a high content of gypsum (45.4%), shown by the d-spacing of 7.609 Å (2-theta 11.63) in the diffractogram. The infrared absorption spectra of MRSG indicate close similarities to mined gypsum. The results of the characterization indicated that MRSG has valuable properties that can promote its use in amending soil fertility constraints on nutrient-deficient tropical acid soils.

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Mineralogical Characterization and Firing Temperature Delineation on Minoan Pottery, Focusing on the Application of Micro-Raman Spectroscopy

Heritage ◽

10.3390/heritage2030163 ◽

2019 ◽

Vol 2 (3) ◽

pp. 2652-2664 ◽

Cited By ~ 2

Author(s):

E. Grammatikakis ◽

Kyriakidis ◽

D. Demadis ◽

Cabeza Diaz ◽

Leon-Reina

Keyword(s):

Bronze Age ◽

Firing Temperature ◽

Raw Materials ◽

Morphological Characteristics ◽

Ceramic Technology ◽

Phase Identification ◽

Mineralogical Characterization ◽

Analytical Protocol ◽

Crucial Information ◽

Analytical Tools

Ceramic objects in whole or in fragments usually account for the majority of findings in an archaeological excavation. Thus, through examination of the values these items bear, it is possible to extract important information regarding raw materials provenance and ceramic technology. For this purpose, either traditional examination protocols could be followed, focusing on the macroscopic/morphological characteristics of the ancient object, or more sophisticated physicochemical techniques are employed. Nevertheless, there are cases where, due to the uniqueness and the significance of an object of archaeological value, sampling is impossible. Then, the available analytical tools are extremely limited, especially when molecular information and mineral phase identification is required. In this context, the results acquired from a multiphase clay ceramic dated on Early Neopalatioal period ΜΜΙΙΙΑLMIA (1750 B.C.E.–1490 B.C.E.), from the Minoan Bronze Age site at Philioremos (Crete, Greece) through the application of Raman confocal spectroscopy, a nondestructive/ noninvasive method are reported. The spectroscopic results are confirmed through the application of Xray microdiffraction and scanning electron microscopy coupled with energy dispersive Xray spectrometry. Moreover, it is demonstrated how it is made possible through the application of microRaman (μRaman) spectroscopy to examine and collect crucial information from very small inclusions in the ceramic fabric. The aim of this approach is to develop an analytical protocol based on μRaman spectroscopy, for extracting firing temperature information from other ceramic finds (figurines) where due to their uniqueness sampling and analyses through other techniques is not possible. This information can lead to dating but also to firing kiln technology extrapolations that are very significant in archaeology.

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Drill-Core Mineral Abundance Estimation Using Hyperspectral and High-Resolution Mineralogical Data

Remote Sensing ◽

10.3390/rs12071218 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1218

Author(s):

Laura Tuşa ◽

Mahdi Khodadadzadeh ◽

Cecilia Contreras ◽

Kasra Rafiezadeh Shahi ◽

Margret Fuchs ◽

...

Keyword(s):

Machine Learning ◽

High Resolution ◽

Ore Deposits ◽

Machine Learning Algorithms ◽

Training Data ◽

Support Vector ◽

Drill Core ◽

Data Types ◽

Mineralogical Characterization ◽

Core Samples

Due to the extensive drilling performed every year in exploration campaigns for the discovery and evaluation of ore deposits, drill-core mapping is becoming an essential step. While valuable mineralogical information is extracted during core logging by on-site geologists, the process is time consuming and dependent on the observer and individual background. Hyperspectral short-wave infrared (SWIR) data is used in the mining industry as a tool to complement traditional logging techniques and to provide a rapid and non-invasive analytical method for mineralogical characterization. Additionally, Scanning Electron Microscopy-based image analyses using a Mineral Liberation Analyser (SEM-MLA) provide exhaustive high-resolution mineralogical maps, but can only be performed on small areas of the drill-cores. We propose to use machine learning algorithms to combine the two data types and upscale the quantitative SEM-MLA mineralogical data to drill-core scale. This way, quasi-quantitative maps over entire drill-core samples are obtained. Our upscaling approach increases result transparency and reproducibility by employing physical-based data acquisition (hyperspectral imaging) combined with mathematical models (machine learning). The procedure is tested on 5 drill-core samples with varying training data using random forests, support vector machines and neural network regression models. The obtained mineral abundance maps are further used for the extraction of mineralogical parameters such as mineral association.

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Developing Alternative Building Materials from Mining Waste

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.976.202 ◽

2014 ◽

Vol 976 ◽

pp. 202-206 ◽

Cited By ~ 1

Author(s):

Javier Flores Badillo ◽

Juan Hernández Ávila ◽

Francisco Patiño Cardona ◽

Norma Yacelit Trápala Pineda ◽

José Abacú Ostos Santos

Keyword(s):

Compressive Strength ◽

Building Materials ◽

Subsequent Treatment ◽

Mining Waste ◽

Mineralogical Characterization ◽

Green Strength ◽

Mineral Phases ◽

Heavy Clay ◽

Industrial Materials ◽

Strength And Plasticity

In this paper we present the production of alternative industrial materials from the mining waste in the form of tailings, this study was made with the tailings of Dos Carlos, establishing 4 sampling zones, dividing them into three strata in the bottom, middle and top. The sampling method used is quartering, to homogenize the material and anticipate the possible use of it as a building material, having for this purpose 12 ceramic mixtures for subsequent treatment. Chemical composition was determined as 70.43% SiO2, 7.032% Al2O3, 2.69% Fe2O3, 0.46% MnO2, 3.98% K2O, 3.34% CaO, 2.50% Na2O, 56 grams per tonne of Ag y 0.6 grams per tonne of Au. In the mineralogical characterization the tailings presents silica, albite, berlinite, orthoclase and potassium jarosite as the main mineral phases, among other mineral phases in lesser concentration such as gypsum, calcite, anorthoclase, pyrite, sphalerite and galena. The determinations of the tailing material granulometry in the range of 60% in a size less than 270 mesh (53 μm). Afterwards, the alternative industrial materials were produced by using the tailings and heavy clay in order to give the composite a good green strength and plasticity during development, but above all to give it a compressive strength similar or higher than that of products derived from conventional processes. Keywords: Tailings, green strength, compressive strength, plasticity, heavy clays, alternative industrial materials.

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