TITLE:
Development and Calibration of a Quantitative, Automated Mineralogical Assessment Method Based on SEM-EDS and Image Analysis: Application for Fine Tailings
AUTHORS:
R. Mermillod-Blondin, M. Benzaazoua, M. Kongolo, P. de Donato, B. Bussière, P. Marion
KEYWORDS:
Automated mineralogy; Stereological corrections; Mineralogy calibration; Acid mine drainage
JOURNAL NAME:
Journal of Minerals and Materials Characterization and Engineering,
Vol.10 No.12,
October
10,
2011
ABSTRACT: Quantitative mineralogy has seen significant developments from the combination of scanning
electron microscopy (SEM) with automatic image analysis and energy dispersive X-ray
spectrometry (EDS). The mining industry is one of the fields that has benefited from this
progress. In this paper, the authors present a newly developed quantitative method based on
SEM-EDS and image analysis (IA), which is used to determine the mineralogical and
environmental characteristics of mine tailings. The main objectives of the method are to be
able to characterize sulphides and carbonates as monomineral particles, which control the
acid generation from the tailings. Pure sulphides, calcite and quartz were blended to make
mineralogical standards that represent typical mine tailings environmental behavior. The
SEM-EDS-IA method achieved good mineralogical precision for medium (1-20 Wt%) and
abundant (> 20 Wt%) minerals, with a relative error below 10 %. However, some
corrections had to be applied to account for typical stereological effects (apparent particle
diameter from polished surface) and preparation modes (particle segregation during resin
hardening). Particle size analysis was used to calibrate the method and identify the
corrections to be applied. Since mineralogical quantifications are based on the area of the
observed particles, the most reliable particle size analyses (also obtained from particle area)
typically lead to the best mineralogical characterization. However, the SEM based
techniques may show some limitations for fine-grained particle quantification (