The Bracarense ceramics are characterized by a fine, pale yellow paste covered with a brownish yellow slip. The name is derived from Bracara Augusta, the Roman town located in the north of Portugal, where this type of ceramic paste was first found and identified. Various forms with the same type of paste occur, such as imitations of sigillata, terra sigillata and thin walls from the Augustus-Tiberius period, and common ware. Later, similar ceramics were also found in other archeological sites, e.g. Aquis Querquennis (Galiza, Spain), which question the location of the production center of this type of ceramic paste.Mineralogical and chemical analyses showed that the majority of the Bracarense shards studied differ from the common ware of the Braga region. Despite minor differences, the Bracarense shards collected in Aquis Querquennis have the same geochemical pattern as those found in Bracara Augusta, i.e. they appear to have been manufactured with the same clay type. The firing products found indicate a kaolin character of the source clay, and point to firing temperatures near 900°C. The Aquis Querquennis shards have greater Br contents, which can be explained by use-wear and/or post-depositional processes, as this site is located in a thermal-water region.
Artigo submetido em outubro/2012 e aceito em novembro/2012 RESUMO A gipsita é um sulfato de cálcio di-hidratado e tem o seu principal campo de aplicação industrial a partir da sua transformação para gesso. No Araripe, as minas apresentam diferentes tipos de minério que submetidos a processos de calcinação diferenciados produzem gesso de qualidade diferenciada. Foram descritas macroscopicamente amostras dos seguintes minérios: a) tipo "rapadura;" b) tipo "cocadinha; c) tipo "Johnson"; d) tipo "estrelinha"; e) o alabastro; f) a selenita, além da anidrita. Apresentam-se, neste trabalho, os resultados das investigações em amostras de alguns dos tipos de minérios conhecidos, utilizandose a Difração de Raios-X na expectativa de melhor compreendê-los, visto que atualmente são diferenciados por aspectos meramente morfológicos. Foram realizadas análises difratométricas em amostras dos tipos Jonhson, Rapadura/Cocadinha e Estrelinha. A análise desses difratogramas diagnostica um material puro, bem cristalizado, identificando como única impureza a presença, embora em pequena quantidade, de anidrita nos três tipos estudados. Ainda é possível afirmar que o teor de anidrita é maior no tipo estratificado, seguido pelo tipo estrelinha e no tipo mais nobre -gipsita tipo Jonhson -, embora com concentração de anidrita nos seus nódulos de coloração cinza azulado, fora dos quais ocorre o menor teor entre os três tipos estudados. ABSTRACTGypsum is a calcium sulfate dihydrate and has its principal field of industrial application from its transformation into plaster. In Araripe, mines present different ore types that subjected to distinguished calcination processes produce plaster in a differentiated quality. Samples of the following minerals were described macroscopically: a)"rapadura" type; b) "cocadinha" type; c) "Johnson" type; d) "estrelinha" type; e) the alabaster; f) the selenite, and the anhydrite. This work presents the results of the investigations on samples of some known types of minerals by using the X-Ray Diffraction in hope of better understanding them, since nowadays they are merely differentiated by morphological aspects. Diffractometic analyses were performed on samples of types "Johnson", "rapadura"/"cocadinha" and "estrelinha. The analysis of these diffractograms diagnoses a pure material, well crystallized; however, a single impurity was identified. Although it is in a small amount, anhydrite was found in all three analyzed types. Moreover, it is possible to affirm that the content of anhydrite is higher in the stratified type, followed by the "estrelinha" type and by the nobler type -gypsum "Johnson" -which although its concentration of anhydrite in its bluish gray colored nodules, out of them it occurs the lowest content among the three studied groups.
The paper aims to describe the quality of mineral water marketed by the population of the metropolitan area of Recife-PE in 2015, regarding the microbiological and descriptive analyzes. We analyzed 70 samples of seven different brands of bottled mineral water in the period from January to April and June to August due year. The samples were divided into thirty-five units for both periods, according to Standard Methods for the Examination of Water and Wastewater, by means of testing the presence or absence (P-A) and Pour Plate Method. Regarding the microbiological analysis of samples of the first period in accordance with Resolution 275/2005 brands A, B and C had their departures REJECTED samples and the marks D, E, F and G were APPROVED. In the second period the marks A, B, C, D and E had their departures REJECTED samples and the F and G brands were APPROVED. The percentage shown in the first period indicates 57.14% (APPROVED) and 42, 85% (REJECTED). In the second period the percentage indicates that 28.75% (APPROVED) and 71.42% (REJECTED). That is, in the second period there was obtained a high percentage of water which has been rejected due to the presence of microbiological bacteria.
<p>In this study aims to present possibilities for utilization of waste of “Blue Granite Sucuru” obtained in the exploration phase and whose field is disabled, located in the Paraiba Cariri, in the municipality of Sumé, PB. It was determined the physical indices of this material that showed the following values: density 2660 kg / m3 ; porosity and absorption 0.26% 0.10%, and these ratios are consistent with those proposed by NBR 15844 - granites requirements for such coating material. Starting from field visits collect materials from the waste, which were crushed and one hundred selected pieces were measured values of their lengths, thickness and width, analyzed in the light of ISO 9654. The coarse aggregate produced shows high percentage of cubic materials (64%) and 36% elongated / lamellar material. Thus, the use of elongated gravel / lamellar in the manufacture of concrete reduces the strength thereof to increase the porosity and the possibility of segregation of the mortar when the density of the material in ways. Therefore, the crushed rock produced from the material even though they have good resistance to weathering actions on account of their mineralogical composition (low content in minerals iron and magnesium oxides and 60% alkali feldspar) can used in the manufacture of concrete, provided it has precautions as to and grain size to prevent them from becoming trapped between the steel bars that make up the armor and hinder the consolidation of the concrete, which may cause problems such as segregation of the mixture and the empty forms. However these same britas not lend themselves to constitute ballast railways, as have 36% of elongated / lamellar particles when, in use, the maximum allowed is 10%. Therefore, a better economic and environmental feasibility of the blocks which are not used with ornamental purpose is possible, in which the waste can be availed in the form of crushed stone for the construction industry.</p>
In the Industrial District of Suape in Pernambuco about 120 m 3 of abrasion mud is being formed every month. This viscous pulp composed of steel grains, hydrated lime, water and rock powder (about 40% of the mass of the block) is produced during cutting of rock blocks and production of plates. The abrasion mud has remarkable iron content, but it does not peril the mechanical performance of red ceramics produced from that. The waste material of rock cutting and polishing contains fine sand particles from the polishing powder. The grading curve of the clay clearly shows the presence of different size fractions. Thus, the abrasion mud can be added to the clay used for ceramic production. Samples of rock dust did not show plasticity and flow properties. The plasticity required in a mass ceramic can be provided by the use of dark clay of high plasticity. The rational use of particular waste decreases the environmental impact of rock cutting and broadens the spectrum of potential raw materials, as well. Farah Diba da SILVA (1977) has graduation in geography and completing the master's degree in mineral engineering at Federal University of Pernambuco. Studies the reuse of industrial solid waste coming from the industry of ornamental rocks and red ceramic.
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