XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 2095
flame at a temperature of approximately 1050 °C and then
poured into a 32 mm diameter 95% Pt/Au molds to cool.
The resulting glass discs were analyzed on a Philips PW2404
XRF system using a control program developed by Philips
and algorithms developed in-house by CSIRO for specific
use on mineral sands products.
Quantitative X-Ray Diffraction (QXRD)
Quantitative X-ray diffraction was carried on micronized
samples of the Ilmenite, Mag. Mix, Non-mags, and Garnet
fractions to determine their mineralogy. Diffraction data
were collected over the range 5–140° 2θ using a Panalytical
Empyrean instrument fitted with a Co X-ray tube oper-
ated at 40 keV and 40 mA. Phase identification was per-
formed using Panalytical Highscore Plus© software (V4.8).
Quantitative phase analysis (QPA) was carried out via
the Rietveld method (Rietveld, 1969) using TOPAS V6
software.
Scanning Electron Microscopy (SEM)
Scanning electron microscopy was used to examine the
mineralogy and textures in the samples. Back-scattered
electron SEM images were obtained using a FEI Quanta
400 FEG-ESEM. The instrument was operated at high vac-
uum (10–5 Torr), an accelerating voltage of 15 keV and a
beam current of 0.3 nA. The chemistry of individual phases
was determined by performing spot energy dispersive anal-
yses with data collected using a Bruker X-Flash 5010 ED
detector.
Electron Probe Microanalysis (EPMA)
The high value ilmenite and zircon concentrates were
mapped using a high resolution field emission gun equipped
EPMA (JEOL 8500F Hyperprobe) to examine the distri-
bution of major and minor mineral phases, and to examine
the chemical homogeneity of the grains. Polished epoxy
resin grain mounts were mapped over a grid of analysis
points using a combination of wavelength dispersive (WD)
and energy dispersive (ED) spectroscopic techniques. The
elemental distribution data was then processed using the
software package CHIMAGE, which incorporates an auto-
mated clustering algorithm that identifies chemically alike
phases (Wilson et al., 2008 Torpy et al., 2018). Groupings
of elements identified via the clustering represent statisti-
cally different chemical/mineral phases and these phases
were overlaid onto the mapped region to provide a phase-
patched map.
RESULTS
Bulk Chemistry of Fractions
The XRF data for the recovered VHM bulk samples repre-
senting the ilmenite, mixed magnetic, non-magnetics, gar-
net, and quartz fractions, are listed in Table 1.
The XRF results for the ilmenite fraction indicated
the concentrate contained 36.2 wt% TiO2 and 53.5 wt%
Fe2O3. Other elements present included: silicon (4.98 wt%
SiO2), aluminium (1.79 wt% Al2O3), calcium (0.89 wt%
CaO), magnesium (0.57 wt% MgO) and manganese
(1.35 wt% Mn3O4). The low TiO2 content as well as the
presence of these oxides/elements as additional compo-
nents in the concentrate suggest silicate and aluminosilicate
gangue phases were present while the high Fe2O3 suggests
Table 1. Chemical analysis results (XRF) of the separated
fractions
Oxide/
Element Ilmenite Mag. mix Non-mags Garnet
TiO2 36.16 6.73 6.81 1.19
Fe
2 O
3 53.53 21.74 8.49 28.35
SiO
2 4.98 38.67 47.58 37.96
Al2O3 1.79 15.50 12.96 18.60
CaO 0.89 7.47 12.22 5.99
CoO n.d. 0.01 n.d. n.d.
Cr
2 O
3 0.12 0.18 0.03 0.05
K2O 0.11 0.51 0.44 0.20
MgO 0.57 3.60 2.31 3.98
Mn
3 O
4 1.35 0.98 0.35 1.98
Na
2 O 0.12 0.56 0.77 0.31
Nb2O5 0.05 0.03 0.03 0.01
NiO n.d. 0.01 n.d. n.d.
P
2 O
5 0.07 1.17 3.27 0.55
PbO n.d. n.d. n.d. n.d.
SnO2 n.d. n.d. n.d. n.d.
SO3 n.d. 0.01 n.d. 0.01
V
2 O
5 0.13 0.05 0.04 0.03
ZrO
2 0.08 1.30 3.88 0.45
ZnO 0.02 0.03 0.01 0.01
CeO2 0.02 1.01 0.54 0.18
La
2 O
3 0.01 0.45 0.23 0.09
WO
3 n.d. 0.02 0.01 n.d.
Cl 0.01 0.03 0.02 0.02
BaO n.d. n.d. n.d. n.d.
Th ppm 20 1710 1180 280
U ppm 10 230 220 50
n.d. =Not determined.
flame at a temperature of approximately 1050 °C and then
poured into a 32 mm diameter 95% Pt/Au molds to cool.
The resulting glass discs were analyzed on a Philips PW2404
XRF system using a control program developed by Philips
and algorithms developed in-house by CSIRO for specific
use on mineral sands products.
Quantitative X-Ray Diffraction (QXRD)
Quantitative X-ray diffraction was carried on micronized
samples of the Ilmenite, Mag. Mix, Non-mags, and Garnet
fractions to determine their mineralogy. Diffraction data
were collected over the range 5–140° 2θ using a Panalytical
Empyrean instrument fitted with a Co X-ray tube oper-
ated at 40 keV and 40 mA. Phase identification was per-
formed using Panalytical Highscore Plus© software (V4.8).
Quantitative phase analysis (QPA) was carried out via
the Rietveld method (Rietveld, 1969) using TOPAS V6
software.
Scanning Electron Microscopy (SEM)
Scanning electron microscopy was used to examine the
mineralogy and textures in the samples. Back-scattered
electron SEM images were obtained using a FEI Quanta
400 FEG-ESEM. The instrument was operated at high vac-
uum (10–5 Torr), an accelerating voltage of 15 keV and a
beam current of 0.3 nA. The chemistry of individual phases
was determined by performing spot energy dispersive anal-
yses with data collected using a Bruker X-Flash 5010 ED
detector.
Electron Probe Microanalysis (EPMA)
The high value ilmenite and zircon concentrates were
mapped using a high resolution field emission gun equipped
EPMA (JEOL 8500F Hyperprobe) to examine the distri-
bution of major and minor mineral phases, and to examine
the chemical homogeneity of the grains. Polished epoxy
resin grain mounts were mapped over a grid of analysis
points using a combination of wavelength dispersive (WD)
and energy dispersive (ED) spectroscopic techniques. The
elemental distribution data was then processed using the
software package CHIMAGE, which incorporates an auto-
mated clustering algorithm that identifies chemically alike
phases (Wilson et al., 2008 Torpy et al., 2018). Groupings
of elements identified via the clustering represent statisti-
cally different chemical/mineral phases and these phases
were overlaid onto the mapped region to provide a phase-
patched map.
RESULTS
Bulk Chemistry of Fractions
The XRF data for the recovered VHM bulk samples repre-
senting the ilmenite, mixed magnetic, non-magnetics, gar-
net, and quartz fractions, are listed in Table 1.
The XRF results for the ilmenite fraction indicated
the concentrate contained 36.2 wt% TiO2 and 53.5 wt%
Fe2O3. Other elements present included: silicon (4.98 wt%
SiO2), aluminium (1.79 wt% Al2O3), calcium (0.89 wt%
CaO), magnesium (0.57 wt% MgO) and manganese
(1.35 wt% Mn3O4). The low TiO2 content as well as the
presence of these oxides/elements as additional compo-
nents in the concentrate suggest silicate and aluminosilicate
gangue phases were present while the high Fe2O3 suggests
Table 1. Chemical analysis results (XRF) of the separated
fractions
Oxide/
Element Ilmenite Mag. mix Non-mags Garnet
TiO2 36.16 6.73 6.81 1.19
Fe
2 O
3 53.53 21.74 8.49 28.35
SiO
2 4.98 38.67 47.58 37.96
Al2O3 1.79 15.50 12.96 18.60
CaO 0.89 7.47 12.22 5.99
CoO n.d. 0.01 n.d. n.d.
Cr
2 O
3 0.12 0.18 0.03 0.05
K2O 0.11 0.51 0.44 0.20
MgO 0.57 3.60 2.31 3.98
Mn
3 O
4 1.35 0.98 0.35 1.98
Na
2 O 0.12 0.56 0.77 0.31
Nb2O5 0.05 0.03 0.03 0.01
NiO n.d. 0.01 n.d. n.d.
P
2 O
5 0.07 1.17 3.27 0.55
PbO n.d. n.d. n.d. n.d.
SnO2 n.d. n.d. n.d. n.d.
SO3 n.d. 0.01 n.d. 0.01
V
2 O
5 0.13 0.05 0.04 0.03
ZrO
2 0.08 1.30 3.88 0.45
ZnO 0.02 0.03 0.01 0.01
CeO2 0.02 1.01 0.54 0.18
La
2 O
3 0.01 0.45 0.23 0.09
WO
3 n.d. 0.02 0.01 n.d.
Cl 0.01 0.03 0.02 0.02
BaO n.d. n.d. n.d. n.d.
Th ppm 20 1710 1180 280
U ppm 10 230 220 50
n.d. =Not determined.