Mineralogical and Microstructural Analysis in Anisotropic Rocks: Gneiss from Erzgebirge as a case of study

Anisotropy is one of the most important features that must be considered in the evaluation for comminution. The evaluation of physical and mineralogical properties provides parameters to optimize the size reduction process using the natural crushing behaviour of raw materials, which is mainly linked to the texture and structure of the rocks. Mineralogical and petrographic characterisation plays an important role and must be as accurate as possible to predict the response of rocks to mechanical stress. This article presents the first results of characterisation using the integration of optical microscopy techniques with numerical description by Quantitative Microstructural Analysis (QMA), three-dimensional characterisation by microcomputed tomography (µCT) and dilatometry experiments. The integration of these techniques primarily aims at seeing the applicability of QMA to anisotropic materials and obtaining textural and structural parameters. The analyses were conducted on gneisses from the Saxony´s mining district, Erzgebirge (Ore Mountains), Germany.

Bravo A. H., Heide G., Popov O., Lieberwirth H. Mineralogical and Microstructural Analysis in Anisotropic Rocks: Gneiss from Erzgebirge as a case of study. MIAB. Mining Inf. Anal. Bull. 2022;(9−1):87—102. [In Russ]. DOI: 10.25018/0236_1493_2022_101_0_87.

The team would like to thank the Sächsische Aufbaubank (SAB) in cooperation with the European Social Fund (ESF, application No.: 100270113) for the funding of the InnoCrush project.

Bravo A. H., Cand. Sci. (Eng.), Researcher, Technische Universität Bergakademie Freiberg (TUBAF) Freiberg, Germany, e-mail : bravo@iart.tu-freiberg.de, ORCID ID: 0000-0002-8125-4760;
Heide G., Prof., Dr. Sci. (Eng.), Head of Institute of Mineralogy, Technische Universität Bergakademie Freiberg (TUBAF) Freiberg, Germany, e-mail : gerhard.heide@mineral.tu-freiberg.de.
Lieberwirth H., Prof., Dr. Sci. (Eng.); Head of Institute for Minerals Processing Machines and Recycling Systems Technology (IART), Technische Universität Bergakademie Freiberg (TUBAF) Freiberg, Germany e-mail : Holger.Lieberwirth@iart.tu-freiberg.de, ORCID ID : 0000-0002-5207-4138;
Popov O., Dr.-Ing., Institute for Minerals Processing Machines and Recycling Systems Technology (IART), Technische Universität Bergakademie Freiberg (TUBAF) Freiberg, Germany, e-mail : Oleg.Popov@iart.tu-freiberg.de.

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