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Characterization of Ecuadorian feldspar by instrumental analytical techniques and statistical calculation of uncertainty for the reliability of results.

Monica Moreno-Barriga, Andrés Noguera-Cundar, Lidia Castro-Cepeda

Article ID: 1970
Vol 2, Issue 2, 2021

DOI: https://doi.org/10.54517/aas.v2i2.1970
VIEWS - 36 (Abstract)

Abstract

The present study has as objective the analysis and characterization of a sample of an Ecuadorian feldspar, by means of XRD, SEM and TGA techniques, for the microstructural analysis of mineral phase and chemical composition. Qualitative and quantitative X-ray diffraction analysis by Rietveld refinement revealed that this feldspar is composed of 33.31% Albite, 15.70% Quartz and a large percentage by weight of 50.99% amorphous material. To validate these results, the uncertainty of the measurement was investigated and calculated by statistical analysis of standard deviation, giving as results an uncertainty error of ±0.87wt%, ±0.23wt% and ±0.89wt% respectively for the percentages by weight of the minerals found in this analysis. The result by SEM shows the presence of Albite in the feldspar exhibiting laminar twinning and characterized by randomly dispersed spherical quartz and plagioclase inclusions.

Keywords

Characterization; Feldspar; Rietveld; DRX; SEM; FT-IR; TGA

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