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This paper shows a contribution to the knowledge of the geological management of ceramic raw material. We have mainly focussed on the clays with a ceramic interest. The article begins with an introduction to the mineralogical determining factor of the ceramic sector. Then, it shows a development of the main steps that take place in the geological prospecting and it concludes with the criteria that must be followed when selecting the outcrops: geographical and environmental conditions, (1) legislation, (2) market and technology, (3) mineralogical and technological characterisation and (4) geological and mining characterisation.

Coal mine restoration projects increase public perception of mining companies. Spain has relatively few examples of completed opencast mine rehabilitation projects. This study seeks to obtain the use of mine spoils from coal mines in Teruel. The studied mine spoils may be used as raw material for the Spanish ceramic industry, located in the provinces of Castellon, Valencia and Teruel. This study specifically discusses the mineralogical and geochemical characteristics of the Lower Cretaceous materials from coal deposits in Estercuel basin, around Teruel and Castellon in Spain. These provinces have a large ceramic industry. A characterization of mine spoils from coal deposits has been carried out. This characterization is based on the data of both mineral and chemical analysis. The mineralogical characterization was complemented with SEM/EDAX. The study of the chemical composition allows the evaluation of the applicability of the studied mine spoils to the following industries: refractory, fine clay, red clay for pavement and coating, and heavy clay. The clay used for refractory industry has the highest compositional demand. The positive results obtained on this set of preliminary tests lead us to envisage new research programs, focusing on testing these mine spoils on a semi-industrial scale.

In southern Chile, with a mild and rainy climate, high levels of heavy metals have been detected in many gold placer deposits. Many of the contaminants pose risks to human life, and consequently damage the trofic chain in this environment. The study zones selected correspond to the handicraft gold-bearing sands of Rio Gato (Los Muermos), Carelmapu and Cucao. These are all located in the X Region of “Los Lagos” in Chile. The type of methodology used in the characterization of the associated mineralization consists of testing each representative sample with a grain size distribution, statistical parameter analysis and a mineralogical analysis, using a binocular magnifying glass, a petrographic microscope, XRD and SEM/EDX. The chemical composition was defined by means of X ray fluorescence and micro-chemical analysis. The results of the study about sediments in southern Chile are presented. The major concentrations of heavy minerals are generally located in areas of dynamic river energy. In the samples, more than 70% of the heavy minerals were distributed among grain sizes corresponding to thin sand with good grain selection (meshes of 0.25–0.06 mm). The main mineral phases present in the analysed samples were gold, zircon, olivine, ilmenite, hornblende, hypersthene, hematite, garnet, chromite, chlorite, augite, amphibolitic-epidote, etc. The main heavy metals found as a result of the study were mercury, lead, cadmium, chrome, tellurium, indium, zinc, cobalt, copper, platinum, gold, etc., and as well some less common elements like cerium, praseodymium, gadolinium, neodymium, samarium and lanthanum. This research work is only a starting point for carrying out a risk probability mapping of heavy metals and the mineralogy of the Cucao, Carelmapu and Rio Gato gold-bearing sands.

The study area is highly industrialized, with businesses involved in the non-metal mineral products sector and ceramic industries (colors, frits and enamel manufacturing) standing out. Air quality evaluation was performed regarding atmospheric particles (PM10 fraction) and Pb in a Spanish coastal area during 2001 and 2002 in order to compare these values with other areas in the Mediterranean basin. Once the samples were collected, their PM10 fraction concentration levels were determined gravimetrically. A Pb analysis in air pollution filters was carried out by ICP-MS. The seasonal and weekly variabilities of these contaminants were also studied, with the objective of being able to explain their origin and thus minimize their possible damaging effects. A similar evolution of PM10 and Pb was observed in both years of the study. Higher PM10 concentrations have been detected during the months of June and July, lower values between March–May, August and October–December, and intermediate values in January and February. A similar tendency has been observed by other authors in European industrialized cities. Regarding Pb, the monthly mean remains constant during the entire year. In the study area, Pb represents 0.6% as a mean of the total PM10 mass, with a variation range between 0.1 and 5.1%. The major crystalline phases in PM10 were quartz, calcite, dolomite, illite, kaolinite and feldspars.

Castellon province houses the nucleus of ceramics production in Spain (93%). This nucleus, located around in the villages of Castellon, Villarreal, Alcora and Onda, has gone through a special process of industrial expansion. The emissions, most of them of particulate material, can constitute a real environmental problem. A study designed to identify the crystalline and glassy phases in the depositable particulate material has been carried out by SEM/EDX and X-ray diffraction methods. Quartz, calcite, illite, kaolinite, chlorite, and feldspars have been the main crystalline phases identified. The number of spherical morphology particles found in the depositable material is remarkable. The vitreous material found was spherical nodules. Due to the shape, size (1–10 μm), and chemical composition of these particles, they can be excellent tracers of the ceramics industry emissions.The presence of Zn, Ba, or Fe are due to the massive use of these substances as opacifying and pigmentation agents in many ceramics frits and glaze compositions. This fact gives a valuable information that will facilitate the studies guided to obtain important aims such as: toxicology, average size of a particle, formation mechanisms, etc.

The necessity of eliminating debris from a granite quarry has awakened an interest in applications of by-products, called “marginal arids”, in different fields, like construction and foundations for roadways, restoration, material for the manufacture of artificial rocks, and artesian products etc. Conclusions obtained from the results of tests carried out by X-ray diffraction of granite quarry by-products in Extremadura, Spain, submitted to different treatments, are established. Test pieces from two quarries are analyzed and compared generally and specifically, for commercial use. Finally, conclusions relating to essays in test pieces and mineral dynamics of marginal arid granite are exposed.

The objective of this work is to assess the concentrations of three factions of air particles (settable particles, TSP and PM10) and the levels of several toxic elements in a clay atomisation industry through aerosol sampling at several points inside an industrial plant. Mechanical activities, which produce diffuse emissions, are the main process of discharge of particles in both indoor and outdoor workplace environments in the atomisation plant. The levels of As, Cd, Pb, Zn, Ba and Ni increase in the zones with higher concentrations of particles and lower ventilation. The concentrations of As and F are not influenced by the recycling processes. The levels of Cd and Pb do not show great enrichment in air particles collected inside the atomisation plant although the content of both elements is associated with ceramic muck recycling. Finally, the content of B in waste water is mainly transferred in gaseous phase to the atmosphere during the process of drying by atomisation.

Total suspended particulate samples (TSP) were collected and concentrations measured during seventeen months in the vicinity of a ceramic industrial area. A method of fractionating was applied to the samples in order to obtain two fractions corresponding to mineral particulate coming from dust emissions (Upper-F fraction) and to amorphous matter (carbon plus small amounts of S, Ca, Fe, etc) coming mainly from traffic and other combustion processes. Also for TSP samples several element concentrations were measured following two previous treatments: extraction of elements mainly associated with the soluble fraction of the samples (B, Fe, P, As, NO2−, NH4+, Cl−, F) and acid digestion for trace metals and elements mainly associated with the non-soluble fractions of the samples (Fe, As, Cd, Ni, Pb, Zn Ca). Seasonal differences and the influence of meteorological parameters (temperature, relative humidity, pressure and wind conditions) on the air pollution levels, particles as well as ions, were studied. Results show different seasonal and weekly evolution for mineral and amorphous carbonaceous particles because of the different origins in dust emissions or combustion processes respectively, and the different physical properties such as size grain. Of the ions analyzed Fe, Ca and Zn were clearly associated to mineral phases and consequently related to dust emissions, and NO2−, NH4+, P, Cl− were related to amorphous matter coming from combustion. Ni and Cd show lower levels than those reported as guideline values and the source is mainly related to the enrichment of these elements in clay materials. B and As content result in elevated concentrations, with the tendency to increase during cold months. The emission of these elements was associated with vaporization or volatilization during high temperature ceramic processes. The original gaseous state is influenced by temperature. In the winter the content for B and As is higher due to enhanced condensation of gas-phase boron onto particles, while in the summer the increase of air temperature results in elevated evaporation.

Contaminating industrial emissions produced by the ceramics industries (including frit and enamel production) can be divided into dust emissions and emissions produced in high temperature activities. Processes of accumulation and precipitation on the substratum, of compounds enriched in certain elements used in this type of industry can occur. The objective of the present work was to identify the contribution of the emissions of the ceramics industries to the atmospheric particulate that is susceptible to depositing on vegetation and accumulating in the substratum. Samples obtained from high volume collectors were studied. Two zones were considered: zone A, a high volume collector located in the municipalities adjacent to the companies that were the object of the study; and zone B, a high volume collector further away from the said companies and adjacent to a power station and a refinery. The analysis techniques were X-ray diffraction, scanning electron microscopy (SEM), and ICP-MS. The results obtained by means of the X-ray diffraction technique showed a high percentage of clays in the samples, minerals used as raw materials (K-Ba feldspar, zircon silicate), indications of high temperature phases, as well as a background noise characteristic of material of low crystallinity. The SEM analysis confirmed the presence of vitreous particles, which are crystalline phases at high temperature typical of the production of a large variety of frits. The results obtained in the chemical analysis demonstrate that (a) the influence of the frits and enamel production on the high concentrations of Zr, Cu and Ce obtained in zone type A compared with zone B; (b) the affect of clays used as raw materials in the ceramics industry can be demonstrated by the high concentrations of Fe, Al and Mg. The weekly evolution showed two series of elements, a characteristic group of dust emissions and another group of tracers from high temperature processes.

The incidence of power station emissions in the composition of the atmospheric aerosols in an urban-industrial area is presented in this study. The Iberdrola (Spanish electrical company) thermoelectric power station is located at Castellon's industrial estate along the Spanish Mediterranean coast. Due to the fact that there are other polluting industries in this region, the present study is also helpful to investigate potential tracers to discriminate the origin and source of particular pollution events. The analysis of air particulate samples, collected on cellulose membrane filters, was carried out by means of the following instrumentation: (1) mineralogical analysis by X-ray diffraction (XRD), (2) morphological study by scanning electron microscopy (SEM/EDX), and (3) chemical analysis by inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS), to carry out quantitative chemical analyses of both major and trace elements. This analysis has allowed the authors to find marker elements, V and Zn, for the power station emissions.