TY - JOUR
T1 - Discriminating hematite and magnetite via Scanning Electron Microscope–Mineral Liberation Analyzer in the −200 mesh size fraction of iron ores
AU - Grant, D. C.
AU - Goudie, D. J.
AU - Voisey, C.
AU - Shaffer, M.
AU - Sylvester, P.
N1 - Publisher Copyright:
© 2018, © 2018 Institute of Materials, Minerals and Mining and The AusIMM.
Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2018/1/2
Y1 - 2018/1/2
N2 - Scanning Electron Microscope–Mineral Liberation Analysis (SEM–MLA) can be used to discriminate between hematite and magnetite in iron ores. However, achieving backscattered electron (BSE) segmentation between the two minerals is difficult for particles ≤75 µm using typical preparation and analysis methods for the MLA method based on a tungsten filament SEM (Quanta 400) with 25 kV high voltage. Preparing iron ore sample mounts using a slow-speed polishing method, and conducting the experiment on a field emission gun SEM–MLA (Quanta 650) with the high voltage setting lowered to 15 kV reduces instrument noise and results in very clean BSE images and segmentation. This method requires new X-ray standards for each mineral at 15 kV because of major changes in the spectra at lower kV. However, once these X-ray spectra are added to the mineral reference list, effective segmentation can be achieved and an accurate analysis obtained.
AB - Scanning Electron Microscope–Mineral Liberation Analysis (SEM–MLA) can be used to discriminate between hematite and magnetite in iron ores. However, achieving backscattered electron (BSE) segmentation between the two minerals is difficult for particles ≤75 µm using typical preparation and analysis methods for the MLA method based on a tungsten filament SEM (Quanta 400) with 25 kV high voltage. Preparing iron ore sample mounts using a slow-speed polishing method, and conducting the experiment on a field emission gun SEM–MLA (Quanta 650) with the high voltage setting lowered to 15 kV reduces instrument noise and results in very clean BSE images and segmentation. This method requires new X-ray standards for each mineral at 15 kV because of major changes in the spectra at lower kV. However, once these X-ray spectra are added to the mineral reference list, effective segmentation can be achieved and an accurate analysis obtained.
KW - Iron ore
KW - automated mineralogy
KW - field emission gun
KW - mineral liberation analysis
KW - scanning electron microscopy
UR - http://www.scopus.com/inward/record.url?scp=85051299746&partnerID=8YFLogxK
U2 - 10.1080/03717453.2017.1422334
DO - 10.1080/03717453.2017.1422334
M3 - Article
AN - SCOPUS:85051299746
VL - 127
SP - 30
EP - 37
JO - Applied Earth Science: Transactions of the Institute of Mining and Metallurgy
JF - Applied Earth Science: Transactions of the Institute of Mining and Metallurgy
SN - 2572-6838
IS - 1
ER -