Quartz sand resources in the Santa Maria Eterna formation, Bahia, Brazil: A geochemical and morphological study

摘要

This study presents an evaluation of the quartz sand occurrences of the Santa Maria Eterna formation, in northeastern Brazil, as a potential source of raw material for silica glass manufacturing. Samples of quartz sand were analyzed by ICP-MS to determine a range of trace elements and establish its chemical purity. The technological potential of the sand was obtained by counting the quantity of bubbles formed during flame fusion over silica plate. Both chemistry and bubble formation indicate that the raw material is suitable for producing silica glass. The work also investigated the composition of fluid inclusions in the quartz grains and the surface micro-texture by scanning electron microscopy. With the results obtained by these procedures, we inferred that the quartz sand was probably formed in a marine environment, by the precipitation of silica in the form of quartz. The main impurities of the samples are probably present in the mineral inclusions implying that purification is possible and probably competitive. (c) 2015 Elsevier Ltd. All rights reserved.