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Minerals, rocks, discontinuities and rock mass
Published in Ömer Aydan, Rock Mechanics and Rock Engineering, 2019
They represent metamorphosed quartzitic sandstone. Pure quartzite is usually white to gray. Quartzites often occur in various shades of pink and red due to varying amounts of iron oxide. Quartzite is very resistant to chemical weathering.
Deterioration of building stones and stone buildings
Published in John A. Hudson†, John W. Cosgrove, Understanding Building Stones and Stone Buildings, 2019
John A. Hudson†, John W. Cosgrove
At some stage, the building was abandoned and left to the ‘mercy of the elements’—resulting in its current state of disrepair. The stone components have weathered well, being a hard crystalline quartzite which is extremely resistant to both weathering and erosion. However, understandably the dry stone wall sheep fold adjacent to the barn is collapsing despite the individual stone blocks remaining virtually unweathered, whereas the cemented walls of the barn are still intact. Slippage of the roof boards to which the slate tiles have been fastened has caused the structural integrity of the barn to have been lost, and it would require the input of more energy to reverse the physical effect of this degradation processes, i.e., by reducing the entropy of the barn but increasing the consequential entropy of the world.
Future of photovoltaic materials with emphasis on resource availability, economic geology, criticality, and market size/growth
Published in CIM Journal, 2023
G. J. Simandl, S. Paradis, L. Simandl
Silicon is a nonmetallic element in Group 14 (carbon family) of the periodic table with atomic number 14. It is the second most abundant element in the earth’s crust by weight (31.14%) after oxygen (Rudnick & Gao, 2014). It can be found in a wide variety of minerals and elemental compounds. Silicon dioxide (SiO2) or silica is one of the most common compounds, forming all quartz polymorphs and varieties, agate, opal, and chert. Quartz is one of the main rock-forming minerals and the main constituent in high-purity sand, sandstone, and quartzite. It is commonly the main constituent of cores of pegmatites and mineralized or barren hydrothermal veins. Silica materials are available on all continents and satisfactory for most common applications, including ferrosilicon and metallurgical-grade silicon (MG-Si). However, in most cases, the silica content of these rocks is too low and the impurities content is too high for direct transformation to solar- or electronic-grade Si.
Pavement smoothness of asphalt concrete overlays
Published in International Journal of Pavement Engineering, 2019
Yetkin Yildirim, Gökhan Saygili
Quartzite is a metamorphic rock. It is made of quartz (silicon dioxide) and sandstone. It is one of the hardest, toughest and most durable rocks known. Because it has high quartz content and requires an anti-stripping agent when used with bituminous materials. Quartzite is excellent in toughness, hardness, durability and chemical stability, is fair in crushed shape, and is fair to good in surface characteristics. Its density is 2.69 g/cm3, which is medium.
Elemental characterization of quartzite of Pouma sub-division of Cameroon and radiation attenuation properties based on XCOM and GEANT4 Monte Carlo simulation
Published in Radiation Effects and Defects in Solids, 2022
Patricia-Laurelle Degbe, Cebastien Joel Guembou Shouop, Daniel Bongue, Merylle Glawdys Beyinda, Maurice Ndontchueng Moyo, Moïse Godfroy Kwato Njock
Quartzites are rocks formed of quartz crystals and defined as siliceous rocks among different commonly used types of rocks (igneous, sedimentary and metamorphic rocks). They come either from the recrystallization of a Quartz strand (gneiss) or from the cementation of a sandstone. They have several applications because of their form, durability, and slice alignment that could be easily separated into thin or thick parts. The density of quartzite varies from 2.6–2.7 g/cm3 or an average of 2.65 g/cm3 (40, 41). The sample selection was justified by the applications of the investigated rocks. Their applications are nationwide acknowledged as these rocks are used in almost every part of the country and worldwide as few importations have been made in neighboring countries. The following list shows a few applications of the quartzite rocks from Pouma (Cameroon): The exploitation of rocks of Pouma makes the main activity of the local population. A flourishing trade of it is being developed locally and the activities of extracting and exporting nationwide contribute to the growth and the development of the locality.Pouma rocks have been recognized as one of the best decorative stones on the world market (EcoMatin. 2018). As the population makes daily use of Pouma rocks in the preparation of dishes (specifically to grind food), it is of great importance to assess these rocks.Used as building materials in the construction of houses, hospitals, and other administrative areas, it is worth valuing the evaluation of the rocks radiation attenuation properties (especially if it is being used in the construction of radiographic test rooms);Their use in manufacturing aggregates for building materials is another asset of the investigated rocks;Other minor applications of these rocks include the non-exhaustive following: manufacturing of tiles for the covering of walls and facades, manufacturing of glasses (Glassmaking company SOCAVER), manufacturing of thermal or acoustic insulation materials, and the use for re-mineralization and fertilization of agricultural soils … etc.