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The Santo Antonio de Padua natural stone cluster in the state of Rio de Janeiro is considered one of the most successful small mining initiatives in Brazil, having seen the creation of around 150 small- and medium-sized companies operating quarries and stone saw mills. Initially used as corral flooring material, the natural stone was later used in large urban projects such as the Porto Maravilha, a project supported by the city of Rio de Janeiro to modernize the city port before the 2016 Olympic Games. Such a step forward was made possible by a multistakeholder approach that brought together local stone business representatives, government agencies, non-governmental institutions, and other authorities that supported a regional development plan stablishing natural stone production as a priority. This paper describes historical events associated with the development of the Padua stone cluster that may offer practical examples for similar initiatives worldwide.

Brazil is one of the main producers and exporters of natural stones in the world. Aiming to contribute to environmental improvements, the life cycle inventory of Brazilian natural stones – LCI Stones was elaborated. This paper presents the results obtained along the LCI Stones project. The project was carried out according to the Brazilian methodology for the elaboration of inventories and to the 14040 and 14044 ISO standards. The study consists of two product systems: quarrying and processing (which is divided in two other subsystems: sawing and polishing), being the last one the main system of this study. The product considered is the polished slab. The data were collected within producing companies, comprising a representative time period for the inventory validation. All inputs and outputs of mass, water and energy as well as products and emissions, within the boundaries, were identified and quantified. The main difficulty found in the data collection was the lack of data control by the companies, mainly the water and energy consumption and polishing inputs. The results of the study showed that, among the stone production processes, gang saw cutting was the one with the most relevant impacts. On account of the rapid technological improvements during the last years, the LCI-Stones is being updated by CETEM.

Sardinia (Italy) produces a vast array of natural stones for ornamental use. Besides the internationally known pink and gray granites and the famous limestone known as Orosei marble, a wide range of vulcanites (basalts and “trachytes”) and phyllites - including yellow and ghiandone granites - are also produced. Orosei marbles are some of the most requested types today, which are marketed especially to China. However, there are a number of Sardinian natural stones, which have been quarried and marketed for fifty years, although no image or footage has been published yet: a mention of this natural stones has been only made in some old list of Sardinian stones. For this reason, authors suggested the publication of a poster (70 cm x 100 cm) showing a collection of natural stones quarried for ornamental purposes in Sardinia over the last fifty years. The poster includes a user-friendly map that has been adapted for school use and as a public resource in libraries. There are no previous publications showing a similar wide range of Sardinian stones. The poster offers scientific information about lithology, quarrying sites, dimension stone producing areas, quarries of historical and/or archaeological interest, historical trend in quarries output, technical properties, stone surface workability and a glossary.

Six Portuguese magmatic ornamental stones were submitted to Soxhlet experiments during 10,000 hours (approximately 416 days) in order to evaluate how the rain water affects the rock behavior as a dimension stone. Macroscopic alterations were observed in the rock fragments and chemical analysis of leaching water solutions revealed how major elements were mobilized from rock-forming minerals allowing to compare weathering susceptibilities between different natural stones.

The receiving of plain problem by analytical appearance with horizontal edges on the endless layer of propagation of the vertical crack and the dependence of the inner pressure of crack is observed. It supposed that the bottom edge of the layer is fixed to absolutely hard semi-flatness, but the upper edge is free. In this respect, we have tried to get the propagation measure of the opening and the analytical aspect of pressure change dependence acting inside it, by method of local modifications using the received solutions. The corresponding methods of approximate illustration of functional dependence are used. In the environment of the opening and the received measure of crack propagation the analytical expressions of distribution of stresses give the full image of peculiarities of those dependences for that immeasurable domain and correspond to the received results by method of modifications. The received formulas may be applied by solving concrete applicable problems and in studies of opportunities of cracks’ propagation for environment of fragile material. Those opportunities are increasing moreover if we take into account that the solutions are received for immeasurable environment.

In the case of material parameters required for evaluation of built heritage preservation state, knowledge of the least possible volume of removed sample is essential in order to minimize damage accumulation to the buildings. These requirements lead to determination of representative volume element (RVE) that was in this paper calculated using combination of image and signal processing techniques. Then, a detailed map of material properties was created using nanoindentation to evaluate local characteristics of the material. Furthermore, atomic composition of samples was quantified by energy dispersive spectrometry (EDX) detector for scanning electron microscopy (SEM) device. Presented method based on combination of SEM, EDX and nanoindentation techniques demonstrates possibility of effective testing in the field of historical buildings preservation.

The alterations to the visual properties of a Spanish limestone, Crema Loja, in relation to its water content are presented, measured and discussed in this work. A Computer Vision System previously developed, validated and patented by CTAP, was used. The study was carried out on different tiles with two surface treatments: polished and honed. A critical value of water content is proposed at the end of the study to avoid problems derived from alterations to the visual properties of this stone material due to moisture.

Natural stone is a raw material widely used, especially in the creation of products in construction and architecture. Currently, this sector suffers tough competition from countries with strong trade structures and distribution channels, which should lead us to rethink new design strategies. The objective of this paper is to find out how Portuguese and Spanish companies work and what they offer; but, it also intends to identify what consumers want, showing the most important aspects of design for the development of competitive products. An overview of the stone sector was achieved through a series of personal interviews with the entrepreneurs from companies that participated in the most representative fairs of the Natural Stone industry in Portugal (PEDRA, Batalha) and Spain (CEVISAMA, Valencia), and through a questionnaire distributed on the internet. A total of 439 valid answers from Portuguese and Spanish consumers were obtained. Companies are rather small and structured in a traditional way. Despite possessing a thorough technical knowledge of the materials, they offer to the market mainly exterior cladding in marble and they do not innovate with new designs and other materials. Consumers demonstrate a broad knowledge of the different types of natural stone and their different applications, expressing a growing interest in the design and creation of new products and new applications. It can be conclude that there is some agreement, but also some differences of opinion, between what is offered and what is wanted. New design products in natural stone that emphasize the resistance, the finishing, the textures and the impermeability of the material will increase competitiveness in the studied markets.

In this study, a new computer program developed to determine the colour properties of natural stone products is introduced. The program can scan any digitalised picture of natural stone products and produce several statistical results such as mean, variance, minimum and maximum colour values, skewness and kurtosis values of the colour histogram, energy, contrast, entropy and homogeneity values of the data which may be used to classify the typology and/or quality of natural stone products. As a case study, Orosei limestones (Sardegna, Italy) were used. There are several typologies of Orosei limestones such as Nuvolato (Cloudy), Venato chiaro (Light veined), Venato medio (Medium veined), Venato scuro (Dark veined), Perlato chiaro (Light pearled), Perlato medio (Medium pearled) and Perlato scuro (Dark pearled). The remarkable results produced by the program are presented.

The main purpose of this work was to increase the knowledge about the geological resources of Trás-os-Montes and Alto Douro region (TMAD), particularly about their “schists” (slate, phyllite and schist), due to the economic and social effects that their mining and processing can have, not only on the local economy, but also on a national level. This work presents the results of the study conducted on “schists” from TMAD, aiming for their use as natural stone. Special emphasis is given on the results obtained from the following physical and mechanical tests: compressive strength, flexural strength, apparent density, open porosity, water absorption, abrasion resistance and resistance to ageing by thermal shock. These tests were determinant to define the most suitable applications for each schistose stone that was studied, taking into account the existing groups of natural stone products. For defining the recommended applications for each “schist”, European standards for natural stone products were considered, as well as technical specifications that exist in some European countries, which were the basis for the establishment of a proposal of technical specifications for Portugal, already published by one of the authors of this work.

This paper discusses in detail the materials properties that should be evaluated for producing large prestressed natural stone cladding panels made of limestone, marble and granite. The work underlines the importance of having standard test procedures used to determine the stone properties employed in the design and dimensioning of prestressed panels. A case-study using 2 types of stones (granite and limestone) is presented to exemplify the application of the stone characterisation under the scope of the technical specification. When safety requirements consider the environmental aspects of the application, the design and dimensioning of the panels must consider the decay of the properties evaluated under the corresponding natural stone specification.

Determining the most convenient plant location is one of the commonly encountered problems in engineering applications. This paper presents an Analytic Hierarchy Process (AHP) model, which is developed for selecting the optimum plant location for marble/travertine factories in natural stones processing industry. The whole criteria which affect the decision making process in marble industry were determined to solve plant location problem in the AHP model. To determine optimum marble plant location for a new marble factory, which is planned to install by a mining firm located in the Eskisehir region in Turkey, an analysis was carried out by introducing the AHP method which is one of the well-known classical Multiple Attribute Decision Making (MADM) methods. This analysis shows that the AHP method can successfully be applied for the selection of plant location as well as any decision making process in natural stone industry.

In cut-off grinding of natural stone the tool performance and stability mainly depends on the self-sharpening behaviour of the cutting segments. Therefore, it is essential to adjust the bonding composition and the process parameters according to the specific separation mechanisms of the work piece material. Different tool wear mechanisms resulting from the different natural stone categories currently avoid the continuous use of one bonding specification. To overcome this limitation an electro-contact discharge dressing (ECDD) process was implemented in the cut-off grinding process. In this way, the backspacing of the bonding can be controlled in-process. The research presented in this paper focuses on the introduction of this technology in the field of stone machining. The demands for applying ECDD in the environment of a stone saw as well as the main influences and interdependencies of ECDD onto the segment topography are discussed.

Metaquartzite from Serra da Garraia and Zebras were studied. These rocks belong to the "Upper Quartzite Formation" of the “Parautochthonous Complex”. They are light grey and present, sometimes, a brownish patina. The quarries range from 2 to 10m high and 25 to 40m long. This study consists on the petrographic, chemical and physical-mechanical characterization of these rocks, aiming the determination of their potential as natural stone. The petrographic studies revealed that the rocks are formed by quartz and white mica and accessory opaque minerals (titanomagnetite, magnetite, and hematite) and zircon. The petrographic studies and SiO2 and Al2O3 values revealed a different evolution for Garraia and Zebras in terms of textural maturity and mineralogical differentiation. The studies allowed the distinction between quartzites and quartz phyllites. The physical-mechanical analyses attest that all the studied rocks can be used as natural stones.

8th Conference of the European-Ceramic-Society -- JUN 29-JUL 03, 2003 -- Istanbul, TURKEY, WOS: 000223059700386, New glaze systems have been continuously developed in order to supply certain advantages to ceramic bodies such as resistance against external thermal and mechanical forces and an aesthetic appearance as well as hygiene. Besides modifying ceramic systems already present, efforts on finding new applicable raw materials and their evaluation are of scientific and industrial importance. The current study was conducted to determine whether the natural stone, the chemical composition of which is 61.55 SiO2, 16.08 Al2O3, 6.18 Na2O, 2.80 K2O, 2.92 CaO, 1.64 MgO, 3.68 SrO, 2.33 ZrO2, 2.82 Fe2O3 (in wt %), can be evaluated in some of colourless and coloured stoneware glazes instead of K-feldspar because of its outstanding fluxing behaviour. At the end of the study ease of its use in the relevant glazes was confirmed., Turkish Ceram Soc, European Ceram Soc

8th Conference of the European-Ceramic-Society -- JUN 29-JUL 03, 2003 -- Istanbul, TURKEY, WOS: 000223059700408, In 1960's the floor tile production of Turkey was started with a large use of K-feldspar as a fluxing agent. However, due to its limited deposits companies begun to employ Na-feldspar instead. At present, considerable level of Na-feldspar is in use. If there are long distances between mines and the factories then transportation costs play an increasing role on the overall production cost. In order to prevent such an occurrence attempts to seek alternative raw material sources have become very important. In this study, a natural stone with high fluxing capability, which is largely available in the regions quite close to the floor tile factories around Eskisehir, was added into floor tile bodies in certain proportion as a replacement of Na-feldspar. Standard tests were applied on the industrially produced floor tiles and results indicated that this stone could be evaluated in floor tile bodies as an alternative-fluxing agent., Turkish Ceram Soc, European Ceram Soc