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Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of GeSec: Revista de Gestao e Secretariado is the property of Sindicato das Secretarias e Secretarios do Estado de Sao Paulo (SINSESP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract The object of this study can be found among the various ornamental rocks used in historic buildings in the city of Rio de Janeiro. It is a degraded Leptinito Gneiss that makes up one of the support columns of the kitchen of the Mosteiro de São Bento (Monastery of Saint Benedict) in Rio de Janeiro. The main aim of the present study is to identify the causes of the high degree of degradation of said column. Non-destructive tests were performed, and laboratory evaluation of the disintegrated fragments may help restore and conserve this column in the future. Results obtained from the tests performed on the altered column were compared to those obtained from another column in the monastery, also built in Leptinito, which is more intact and is a sound Leptinito Gneiss. The results showed that degradation of the column is caused by the crystallization of salts (halite) inside the rock, which is reducing its mechanical strength and causing an imminent risk of collapse.

The purpose of this study was to carry out a mineralogical, chemical, petrographic and physical-mechanical characterization of the two kinds of slate rocks from Tchihingue deposit in Angola in order to make a good use of them as industrial rocks. The characterization was carried out using Atomic Absorption Spectrometry, thin section petrographic analysis and X-ray diffraction. Determining physical-mechanical properties of the rock was carried out through the abrasion test, and resistance to flexion and compression. It was determined that slates have a majority chemical composition of silicon, aluminum, iron and potassium oxides. Both types have a very fine texture on a sericite matrix, which classifies them as sericitic slates. They are essentially composed of muscovite and quartz. Kaolinite is identified on the yellow slate and hematite on the brown slate as accessory minerals, distinctive features of each slate. Brown slate is richer in micaceous minerals and yellow slate has higher quartz content. The technological properties of these slates are suitable for application as an industrial rock, with little significant difference in flexural strength. The selection of its potential can be given from the aesthetic point of view. [ABSTRACT FROM AUTHOR]

Solid waste management in the ornamental rock sector is of great importance given the enormous amount of waste generated in the process, which on average reaches the range of 65 to 75%. In addition to representing losses in production, tailings affect the environment and the waste of mineral resources, causing a great socio-environmental impact. Since the tailings are deposited and stored improperly, it damages the very sequence of the extraction work and also creates risks of accidents. Regarding the methodology, a case study was carried out in an ornamental rock quarry located in the Mufumbo site, in the city of Parelhas, RN. Initially a bibliographic survey was carried out in scientific articles, periodicals, annals of congresses, books, theses, dissertations, laws, standards, and manuals on the topics discussed here. It was found that the processes associated to the economic activity of the mining are responsible for the generation of solid, liquid and gaseous wastes, causing environmental compromise, which can sometimes be irreparable. In the present case, the extraction of ornamental rocks is a procedure that generates large volumes of solid waste, so that its use must be promoted through the use of materials that can be used and marketed. [ABSTRACT FROM AUTHOR]

Iron ions with the energy of 40 keV have been implanted into colorless natural rock crystals to high fluencies of 1.0∙1017 and 1.5∙1017 ion/cm2. These crystals were selected from Svetlinsky deposits of the Southern Urals, which are well-known as minerals with high quality and low content of impurities. A radical change in the color of the crystals after iron-ion implantation and subsequent high-temperature annealing in air has been revealed. The origin of color changes has been studied by using optical methods, as well as Mössbauer and X-ray photoelectron spectroscopy. It has been established that the high-dose and high-energy flow of ions results in the formation of various kinds of structural defects on the surface layer of the matrix, such as electron-hole centers, as well as in the formation at a specific depth of the irradiated matrix of the ultrafine iron-containing phases with a structure, which is non-coherent to the structure of the original matrix. The subsequent high-temperature annealing of the implanted quartz has changed the color of the samples to orange-yellow. This color is similar to the color of natural citrine. The orange color richness of the heat-treated samples grew with increasing amounts of embedded iron impurity in the crystal. The nature of orange-yellow coloration of the implanted and annealed quartz plates can be explained by the formation of ultrafine hematite nanoparticles located in a layer at a depth of ~15 nm. The possibility of refining the color of minerals by ion-beam exposure has been discussed.

The shear behavior of the discontinuities of rock is important because it is closely related to the stability of a rock mass. The scientific challenge lies in the understanding of how different types of joint are related to the failure criterion. In the current study, direct shear tests are used to investigate the shear behavior of continuous planar joints, stepped joints, and discontinuous open joints. The joints were cast in a synthetic rock made of plaster, sand, and water and tested under normal stresses that ranged from 50 kPa to 3.5 MPa. The shear behavior of both the continuous and discontinuous joints has been found to be dependent on the normal stress. At normal stresses above the magnitude of the tensile strength, continuous and discontinuous joints displayed either strain weakening or brittle behavior. Results with the combination of all joint types indicated that the shear strength of the different types of joint increases sharply at low normal stress, and then approaches a lower bound residual strength envelope at high normal stress. At normal stresses of less than the tensile strength (1.84 MPa), the strength is dominated by cohesion, while at normal stresses greater than the tensile strength, friction appears to dominate the shear strength. For open joints, the shear stiffness is independent of the normal stress. For closed joints, the shear stiffness will increase as the normal stress increases, particularly evident below a normal stress of 1 MPa. Increasing the normal stress reduces the brittleness index of rock samples from 1 to 0. A primary reason for this non-unique failure envelope was the large dilation that occurred at high normal stresses. This dilation was attributed to grain crushing, and the roughness resulting from this crushing and gouge formation as shearing occurred. [ABSTRACT FROM AUTHOR]

Abstract Granites are widely used in construction and they may be potential sources of ionizing radiation, due to the presence of radionuclides such as 40K and decay products from 238U series and 232Th series. These radionuclides occur in the minerals constituting the rocks. To evaluate the doses in humans exposed to 40K, and decay products from 238U series and 232Th series γ radiation, a room with dimensions of 4.0 × 5.0 × 2.8 m3, with uniformly distributed radiation source on the floor of granitic rocks, was computationally modeled. Adult individuals were represented in the virtual scenario by two virtual anthropomorphic phantoms FASH3 and MASH3, incorporated simultaneously in the software MCNPX 2.7.0. The mean energy deposited on each organ and tissue of FASH3 and MASH3 phantoms was determined using the MCNPX F6 tally (MeV/g/particle), while the photon flux within the room was calculated with the MCNPX F4 tally (MeV/cm2/particle). The organs that obtained the highest conversion coefficients CC[H T ] (Sv/Gy) were the red bone marrow (0.94), skin (0.90), breast (0.81) and bladder (0.73) for the FASH3; skin (0.89), gonads (0.88), breast (0.79) and bladder (0.70) for the MASH3. The simulated air absorbed dose rates varied between 23.4 (11%) and 25.8 (12%) nGy/h, and the annual dose rates were 0.10 (6%) and 0.11 (6%) mSv/year. These results presented acceptable statistical uncertainties and they are in agreement with the literature. Fluency of photons pointed to the central region of the room floor as the place of greatest exposure. The results showed that the organs closer to the radiation source had the highest deposited energy values. Based on the annual effective dose data obtained, it was possible to note that the values are within the literature. We believe that the methodology used will allow the investigation of any ornamental material that emits natural radiation. Highlights • Granites are widely used and may be potential sources of ionizing radiation. • The main sources are the 40K, 238U series and 232Th series radionuclides. • The doses in humans to these sources was modeled with the MCNPX code. • Adult individuals were a male (MASH3) and female (FASH3) virtual phantoms. • The highest value of CC[H T ] was for the skin. [ABSTRACT FROM AUTHOR]

The market interest in ornamental rocks commercially referred to as "stones" has grown significantly in recent years, particularly regarding basalt. This has resulted in the widespread use of diamond wire equipped with sintered diamond beads for precision sawing in basalt quarries, especially those located in the industrialized countries; it also has the advantage of preventing rock damages. Diamond wire has been widely used in up-line cutting and other sawing works in both marble and granite quarries for decades; therefore, performance data about the use of this tool on these two different types of rocks are widely documented in academic literature. However, for basalt sawing, information pertaining to the use of diamond wire is unavailable due to various reasons, but mostly because of to its relatively recent introduction in the basalt quarries and also to the historical low market demand for processed basalt in the past. This study offers a possible solution to this lack of information and provides a technical, economic and environmental assessment of diamond wire used in quarrying basalt for ornamental purposes. After an overview on the state of the art of diamond wire and on the final use of processed basalt, the study describes the experimental plan and the results. These show a tool yield much higher than those measured when diamond wire is used on other silicate dimension stones (e.g. granites). Moreover, the composition of basalt sawdust (sludge) has been analysed in the laboratory and has indicated the absence of polluting materials related to tool wear; therefore, basalt sludge, which is made of water and micronized basalt, can be used as a secondary raw material for the environmental restoration of the area or for any other purpose. Further research on other lithotypes is also proposed. [ABSTRACT FROM AUTHOR]

The article offers the author's insights on topics related Chinese gardens design. Topics mentioned include the features of Chinese gardens including winding pathways through areas of rocks and water and several kinds of plants and trees, the quality of Chinese gardens, and the architecture and interior design of gardens in the country. Also mentioned are the design of Suzhou Museum by architect I. M. Pei, the design of the interior environment of the museum that creates connection to the outside stands of stone, trees, and water, and the several orders of design including signs, things, and actions.

The purpose of this study is to characterize the marmored limestone of Bottichino I deposit from the geomechanical point of view in order to update the parameters of the exploitation system. The parameters of the geomechanical classification of Bieniawski (1979) were determined as well as the cracking characteristics, obtained from the geological field survey and processed with the DIP V.5 software. Subsequently, the topographic updating of the deposit was modeled and the spatial representation of the main cracking systems in the three exploitation fronts was made, using the GEMCOM 6.5 software. As a result, the 3D spatial representation of marmored limestone blocks and the main directions of the cracks was obtained, identifying 3 families of predominant cracks, with natural block sizes from medium to large; the rock mass classified as good quality. Advancing directions of the mining front were defined by the determined geomechanical parameters and the recovery of monoliths was also bettered up when having a greater knowledge of the solid structure. [ABSTRACT FROM AUTHOR]

Low yields in ornamental rock mining remain one of the most important problems in this industry. This fact is usually associated with the presence of anisotropies in the rock, which makes it difficult to extract the blocks. An optimised planning of the exploitation, together with an improved geological understanding of the deposit, could increase these yields. In this work, marble mining in Macael (Spain) was studied to test the capacity of non-destructive geophysical prospecting methods (GPR and ERI) as tools to characterize the geology of the deposit. It is well-known that the ERI method provides a greater penetration depth. By using this technique, it is possible to distinguish the boundaries between the marble and the underlying micaschists, the morphology of the unit to be exploited, and even fracture zones to be identified. Therefore, this technique could be used in the early stages of research, to estimate the reserves of the deposit. The GPR methodology, with a lower penetration depth, is able to offer more detailed information. Specifically, it detects lateral and vertical changes of the facies inside the marble unit, as well as the anisotropies of the rock (fractures or holes). This technique would be suitable for use in a second stage of research. On the one hand, it is very useful for characterization of the texture and fabric of the rock, which allows us to determine in advance its properties, and therefore, the quality for ornamental use. On the other hand, the localization of anisotropy using the GPR technique will make it possible to improve the planning of the rock exploitation in order to increase yields. Both integrated geophysical techniques are effective for assessing the quality of ornamental rock and thus can serve as useful tools in mine planning to improve yields and costs. [ABSTRACT FROM AUTHOR]

The objective of this paper was to evaluate the radiological risk index of ornamental rocks sold both in Brazil and Europe and to correlate its radioactive content with their chemical composition. The 238U, 232Th and 40K mean values were 62 ± 65, 122 ± 111, 1126 ± 516 Bq kg-1 for Brazilian and 93 ± 59, 70 ± 67 and 1005 ± 780 Bq kg-1 for Swiss samples, respectively. The radiological index: radium equivalent, external hazard index, absorbed dose rate in air, annual gonadal equivalent dose, annual effective dose equivalent and excess lifetime cancer risk for Brazilian and Swiss samples were calculated. The main contribution for the radiological indices observed was the radionuclide 232Th, which is associated with REE, Br, Hf, Na, Rb, Sb and Zr in the rock matrix.

The sawing process of granite samples from thirty-eight kinds of rocks by a diamond multi-wire saw in an ornamental rock processing plant in the city of Nova Venécia, Brazil was studied using data collected in situ . It was proven that the ratio between the total volume of stone processed and processing time has a strong relationship, a Spearman coefficient absolute value higher than 0.55, with energy consumption and hardness. Thus, it is possible to include energy consumption, hardness and time in a single coefficient. Samples with higher, lower and average values for the proposed coefficient were studied by X-ray diffraction and quartz content was found to be directly related to both the proposed coefficient and hardness. [ABSTRACT FROM AUTHOR]

The ornamental rock processing is carried out mainly using diamond tools. These are currently being produced by powder metallurgy (PM) techniques from diamond and blend powders. In view of the diversity of materials processing routes available, natural materials, and the different processes used in rock processing, diamond tools best suited to each material require formulation of specific compositions capable to achieve suitable performances at a cost as low as possible. [ABSTRACT FROM AUTHOR]

In this work, we present the results of the measurement of the effectiveness of two silanes-siloxanes based products applied on roofing slates with the aim of slowing down the oxidation of the iron sulphide inclusions. The products were applied by immersion and spraying and also at different dilutions. The effectiveness of the treatments were evaluated by means of static contact angle measurements and water absorption coefficient variations; also, the durability under thermal cycles and the colour variations before treatment and before UVA exposition were tested. In all the cases, a very low product consumptions were obtained, due to the particular porous system of these rocks; also, any of the treatments increased the static angle. Nevertheless, the products tested remarkably increased the resistance of sulphides to the oxidation during thermal cycles without producing important changes in rock colour and also they have shown a good durability under UVA exposition

We present a detailed characterization of two calcareous stones from Andalusia (Southern Spain), namely Escúzar calcarenite and Olivillo travertine. Both materials can replace two stones extensively used in the architectural heritage of Andalusia, i.e. La Escribana calcarenite and Alfacar travertine. To establish the suitability of the replacement of ancient materials, detailed examination was performed. X-ray diffraction, X-ray fluorescence, optical and scanning electron microscopy, hydric tests, mercury intrusion porosimetry, gas adsorption, ultrasounds and colorimetry were applied. The Escúzar calcarenite has large pore cavities and higher open porosity than La Escribana calcarenite. From a chromatic point of view both calcarenites are rather similar. The Olivillo travertine is a massive well cemented and heterogeneously colored rock. The ultrasounds velocities for this material are very homogeneous and elevated, indicating excellent mechanical properties. However the hydric and chromatic differences between both travertines point to reduced adequacy of Olivillo travertine as substitutive material for Alfacar.

Copyright of Revista Eletrônica de Materiais e Processos is the property of Revista Eletronica de Materiaia e Processos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Geominas is the property of FUNDA-GEOMINAS. (Fundacion de Egresados d Amigos de la Escuela de Ingenieria Geologica y de Minas) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The suitability of granite conservation treatments (consolidation and/or water-repellency) wide/y used to protect heritage structures was evaluated on the basis of the changes occurring in the intrinsic characteristics of the stone (imbibition capacity open porosity total water-accessible porosity water vapour permeability and capillar absorption coefficient). A statistical analysis conducted of the values obtained for these properties/ which showed differences in fluid flow through the rocks/ found that the application of consolidants followed by water repellency treatment was more effective than either procedure alone, substantially enhancing the properties of the stone from the standpoint of its use as a construction material.

The effluent of the ornamental rock industry is characterized by presenting great concentrations of total solids, high contents of iron, and elevated pH, all responsible for the contamination of the superficial and ground waters, destruction of the soil, the vegetation, and the silting of the rivers. The purpose of this study is to assess the cytotoxic and genotoxic effects and the anatomical changes caused by the effluents arising from the ornamental rock polishing industry in root apex cells of Allium cepa L. (Amaryllidaceae). The samples of the effluent were collected in a polishing industry located in Nova Venécia, State of Espírito Santo, and were analyzed by mass spectrometry and atomic emission. Bulbs of A. cepa were exposed to the effluent at 12.5, 25, 37.5, 50, 75, and 100 % concentrations (residue in raw form) ( v/ v) for a period of 20 days. For the positive control, metilmethanesulfonate (MMS) at 4 × 10-M concentration was used, and distilled water was used for the negative control. The experiment was assessed taking into consideration the following parameters: mitotic index, frequency of chromosomal and nuclear abnormalities in the root apical meristem, and root anatomy. The mitotic index suffered a decrease proportional to the increase in the concentration of effluent. All the concentrations of the effluent led to chromosomal and nuclear abnormalities being stickiness and nuclear shoots the most frequent. The root apex evidenced changes that reflected on the decrease of the percentage area of the protoderm and the fundamental meristem and the increase in the areas of the cap and quiescent center. The symptoms of toxicity are related to the high frequency of cell in cellular death process observed in the roots exposed to the higher concentrations and to the decrease in the mitotic index of the apical root meristem. [ABSTRACT FROM AUTHOR]

Gris Pulpis is a Jurassic microcrystalline limestone found in the Maestrazgo Area of the Iberian Mountain Range (province of Castellón, Spain). This paper reports the results of a detailed study of the mineralogical, pelrographic and chromatic characteristics, as well as the durability, of this stone, classified as a commercial marble for its polish ability. The study determined the relationship between the structural characteristics of the stone, with a proliferation of stylolites and veins, and its physical properties. Its flexura I strength was found to be greater than would normally be expected in a structure with such a dense web of stylolites and veins. This is due to the structural and mineralogical properties of these stylolites, characterised by an extremely wavy design, scant mineral infillings and, occasionally, subsequent cementation. The characteristics of the porous media of homogeneous microcrystalline limestones such as Gris Pulpis largely explain the durability of this stone when exposed to freeze-thaw cycles and salt crystallisation. These arc the properties that make Gris Pulpis limestone, quarried in the Spanish Region of Valencia, a valuable building material for both architectural and civil engineering applications

This paper is an attempt to delineate the ways of nowadays industrialization of ornamental Rocks in Santo Antônio de Pádua (RJ) It is very important to emphasize the almost total dependence of the local economy with this kind of activity.

This paper is an attempt to delineate the ways of nowadays industrialization of ornamental Rocks in Santo Antônio de Pádua (RJ) It is very important to emphasize the almost total dependence of the local economy with this kind of activity.

The objective of this study was to examine the ability of a solid waste produced during beneficiation of ornamental rocks to remove mercury (Hg) from an industrial effluent and aqueous solutions under various conditions. Batch studies have been carried out by observing the effects of pH, concentration of the adsorbate, contact time, and so on. Various sorption isotherm models such as Langmuir, Freundlich, and Tóth have been applied for the adsorbent. Film and intraparticle diffusion were both found to be rate-limiting steps. Adsorption was properly described by the Freundlich model (capacity constant of 0.3090 (mg g−1)(mg L−1)−1/nand adsorption intensity indicator of 2.2939), which indicated a favorable sorption and encouraged subsequent studies for treatment of Hg-containing industrial effluent. Industrial effluent treatment efficiency reached Hg removals greater than 90% by using ornamental rock solid waste (ORSW). Besides, desorption studies indicated that the maximum recovery of mercury was 100 ± 2% for 1 mol L−1HNO3and 74 ± 8% for 0.1 mol L−1HNO3. The ORSW could be reused thrice without significant difference on the Hg removal rate from industrial effluent. These findings place ORSW as a promising efficient and low-cost adsorbent for the removal of Hg from aqueous solutions and industrial effluent. [ABSTRACT FROM AUTHOR]

In this short note, we share a series of reflections on Roman marmora and its use in the Roman Empire, particularly in Baetica. We give a new, more comprehensive perspective on the phenomenon of marble in the Roman world, focusing on its importance for the Roman province. We also analyze the different materials that we have found in various archaeological interventions surpeninsular province with the aim of documenting the marble types used and determined which are the main Mediterranean areas that supply these materials to the region. We mainly focus on the import and marmora the most significant stone materials that were exploited in the Baetica. [ABSTRACT FROM AUTHOR]

Technological characterization is of great importance for rocks used as coating stone. It should be performed soon in the mineral exploration stage, when the type of application should have already known. In this work, the study of the most interesting properties to its application will be put forward: density, porosity, water absorption, uniaxial compressive strength, flexural strength and impact resistance. The aim of this article was to caractherize a pegmatitic igneous rock commercially called " Exotic Fuji" Granite, wich occurs in the city of Pedra Lavrada, state of Paraíba. The results were compared to the limit values suggested by standards and literature. [ABSTRACT FROM AUTHOR]

Straddling between two contrasting structural features, the High-Atlas in east and the Tadla plain in west, the Beni-Mellal region has a diversified and enormous potential in terms of natural resources, especially building materials and ornamental rocks. The material quarries became widespread and represent one of the significant economic activities in the region. The aim of this study was to develop a GIS-database that includes several themes (layers) in order to properly locate all exploited quarries in the Beni-Mellal region and to analyze its relationship with geology, hydrographic and road networks, and market area. The material extraction takes place by the open-pits in rivers and by the quarries in the Atlas piedmont. The majority of aggregate such as sand and gravel is produced from alluvial deposits, flood plains, and stream terraces located along the Oum Er-Rbia and Oued Derna Rivers and its tributaries. The quarries located in the Atlas piedmont produce crushed rock aggregates from limestone and brecciated dolomite rocks of Lias age. More easily accessible, they could provide long-term quarry material production (in tonnage and quality), meeting the needs of the inhabitants of the region. Also, the Beni-Mellal Atlas region offers huge reserves ornamental rocks, namely travertine and limestone onyx deposited in the dolomite and coral-reef limestone of Lias. [ABSTRACT FROM AUTHOR]

Although a significant body of knowledge about the strategies that companies use in their interactions with their environments exists, much less is known about the political dynamics of these interactions in situations of co-evolution between companies and environments. In this case study, we analyze the interactions between the representatives of producers (RPs) of ornamental rock and government authorities (GA) in the Brazilian state of Espírito Santo (ESS). These interactions involved the regulation of heavy cargo transportation and resulted in a significant reduction in road accidents. In this analysis, we replicate a recently published case (Child, Tse & Rodrigues, 2013). Replicating cases is important to establishing validity and extending the generalizability of theoretical results (Vissak, 2010). However, replication is seldom conducted (Pacheco, York, & Hargrave, 2011). We address the following questions: Are the conclusions of Child et al. (2013) compatible with our observations in ESS? Do their concepts help explain the political dynamics of this current case? We conclude in the affirmative to these three questions but identify differences that are attributable to the differing contexts of these situations. [ABSTRACT FROM AUTHOR]

Copyright of Revista Tamoios is the property of Editora da Universidade do Estado do Rio de Janeiro (EdUERJ) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose – The purpose of this research is to determine the major environmental impacts and, especially, to evaluate the geochemical characteristics of water of the lakes formed in abandoned quarries of ornamental rock of the Campo Belo Metamorphic Complex. Design/methodology/approach – To do so, 12 quarries were chosen to be studied. They were mapped in a detail scale and their rocks were described and sampled for petrography analysis. Whenever present, the lakes were evaluated too. In situ measurements included pH, Eh, conductivity, resistivity, total dissolved solids and temperature. Water samples were collected to determine alkalinity, sulfates, chlorates, turbidity, suspended sediments and the concentrations of major and trace elements using the ICP-OES. Findings – Abandoned open-pit mining operations have resulted in the creation of numerous pit lakes. About 90 per cent of the quarries visited and studied were abandoned or interdicted by environmental organs, what will probably lead to its subsequent abandonment. The quarries Borges and Gêmeos were two quarries of the abandoned quarries in the region, which has a lake formed in its trench. Gêmeos and Borges pit lakes analytical data shows clear correlation between the chemical compositions of the solute and the geological characteristics of the quarries. In spite of the differences found, the results showed a relatively quality water according to Brazilian legislation control values. Originality/value – This was the first study done of pit lakes formed in abandoned ornamental rock quarries of Campo Belo Metamorphic Complex/Minas Gerais – Brazil. This research provides a better understanding of the gneisses pit lakes hydrogeochemistry, a subject neglected in scientific literature. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a study of the geometrical design of optimum cutting shapes in granite or marble slabs with the aim of improving cutting operations and reducing tailings in ornamental stone sawshops. To do so, a theory is developed to determine the neutral region of a planar domain using polygonal balls. The neutral region of a planar domain is defined on the basis of geometrical concepts such as the oriented directional distance, the polygonal ball and equidistance with respect to a polygonal ball. Starting out from said neutral region, a polygonal pattern of maximum area may be situated within the polygonal boundary that delimits the ornamental stone. A computational algorithm is implemented to solve this problem is presented, along with some practical examples of cutting granite slabs to validate the theory developed here. [Copyright &y& Elsevier]

The effect of marbles and granites on the plasticity and bending stress of two Mozambican clays (OUA and CIMOC) was studied. For that purpose, clay masses with addition of marble and granite rejects have been prepared, their plasticity and mechanical strength determined. While CIMOC clay results showed a non-regular behaviour, OUA clay, clay with high plasticity, exhibited a regular decrease of plasticity with increasing amounts of additives on one side, improving processability. Bending stress results obtained with OUA clay showed no significant differences for the various additives used on the other side. The results obtained with OUA clay are desirable since residues processed on each day at the respective factory represent a mixture of different marbles and granites with varying (unknown) compositions. This difference in composition has apparently no additional effect on the bending stress of fired samples of OUA clay masses. [ABSTRACT FROM PUBLISHER]

The article presents a study which was carried out to use the experimental design in Simplex Lattice to evaluate the effect of the addition of ornamental rock waste as filler in the composition of ternary mixtures, leading to maximum compaction. The complete cubic simplex model showed to best fit to the experimental results, which results in more statistically appropriated responses to the studied compositions.