Download - Andina Q132 Oct09 (2)
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SGS -Chile Puerto Madero 9600 Parque Industrial Puerto Santiago, Pudahuel, Santiago Chile Tel: +56-2-747 0140 Fax: +56-2-747 0144 www.sgs.com
Member of the SGS Group (SGS SA)
An Investigation by QEMSCANTM into
TTHHEE MMIINNEERRAALLOOGGIICCAALL CCHHAARRAACCTTEERRIISSTTIICCSS OOFF TTHHEE FFEEEEDD SSAAMMPPLLEE
FFRROOMM TTHHEE AANNDDIINNAA PPRROOJJEECCTT
prepared for
AAMMIINNPPRROO
Project OL4320 Q132 Report n1 October 1, 2009
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Table of Contents
Page No.
Table of Contents ii
List of Tables iii
List of Figures iii
INTRODUCTION iv
1 Sample Receipt and Preparation 5
2. QEMSCAN Setup, Operational Modes and Quality Control 5
3. Modal Analysis and Grain Size Distribution 3
4. Copper Ocurrence 4
5. Liberation 11
5.1. Chalcopyrite Liberation 11
5.2. Molybdenite Liberation 12
6. Associations 14
6.1. Chalcopyrite Association 15
6.2. Molybdenite Association 18
Summary of Results 20
Appendix : Assay Reconciliation 21
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List of Tables
Table 1: Sample Identification 5
Table 2: Summary of Operational Statistics 6
Table 3: Modal Analysis and Grain Size Distribution 8
List of Figures
Figure 1: QEMSCANTM
and Direct Assay Reconciliation 6
Figure 2: Bulk Modal Distribution 9
Figure 3: Elemental Cu Deportment as CuT (left). Cu Distribution at 100% (right) 10
Figure 4: Chalcopyrite Liberation in Samples 11
Figure 5: Image Grid of Chalcopyrite Liberation 12
Figure 6: Molybdenite Liberation in Sample 13
Figure 7: Image Grid of Molybdenite Liberation 13
Figure 8: Chalcopyrite Association Distribution 15
Figure 9: Image Grid of Chalcopyrite Associations 16
Figure 10: Examples of Chalcopyrite in association with Pyrite 16
Figure 11: Examples of Chalcopyrite in association with Hard Silicates 17
Figure 12: Examples of Chalcopyrite in association with A) Hard Silicates/Phyllosilicates and B)
Phyllosilicates
17
Figure 13: Examples of Chalcopyrite in association with Fe-Ti Oxides/Oxyhydroxides 17
Figure 14: Molybdenite Association Distribution 18
Figure 15: Image Grid of Molybdenite Associations 19
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Introduction
This summary report describes a mineralogical test program using QEMSCANTM technology
(Quantitative Evaluation of Materials by Scanning Electron Microscopy), conducted in one feed
sample of the ore from Andina project, and submitted by Peter Ameluxen. The purpose of this
test program was to identify mineralogical characteristics, as liberation and association of the
sample. This program was conducted concurrently with the metallurgical test program OL4320,
led by Cecilia Gonzlez.
Mauricio Belmar, Ph.D. Project Mineralogist Advanced Mineralogy Facility Leticia Villagrn Mendoza Geologist Advanced Mineralogy Facility
Sample Preparation by: J. Diaz QEMSCAN
TM Operation by: L. Villagrn
Data Processing by: L. Villagrn Report preparation by: L. Villagrn
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Testwork Summary
1. Sample Receipt and Preparation
One (1) sample from the Andina project identified as Feed was received by the Mineralogy
Department and assigned the LIMS number OL4320 Q132. Sample identification is present in
Table 1. A portion of each fraction was submitted for chemical analyses (Cu, Fe, Mo, S) for
data validation and reconciliation purposes. These results are presented in the assay
reconciliation section of this report.
One graphite-impregnated polished epoxy grain mount was prepared. This polished section was
submitted for analyses using QEMSCANTM technology.
Table 1: Samples Identification
Sample Identification
Alimentacion Linea Convencional 30%Alimentacion Linea Sag 70%
Comp Alim Ro1
4320 - Q132 Andina
2. QEMSCANTM Setup, Operational Modes and Quality Control
The polished sections were analysed using the Particle Mineralogical Analysis (PMA) method in
order to ensure that all copper-bearing minerals, including non sulphides minerals, were
characterized. This method is a particle mapping mode of measurement which allows for
complete mineralogical analysis of the samples and also for a robust determination of the bulk
mineralogy, with minerals identities and proportions, along with average grain size
measurement. The PMA mode also provides an analysis of the special details of minerals,
including liberation and association details.
For the sample, 19.251 particles were analysed using the PMA mode of operation, creating
862.382 points from which the mineralogical info has been derived. The operational statistics of
these analyses are presented in Table 2.
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Table 2: Summary of Operational Statistics
Batch ID
SIP ID
Analysis Type PMA
Fraction Sections Pixel Particle Points
m No. Size (m) No. No.
Comp Alim Ro -212/+3um 1 4,0 19251 862382
Q132
STGO_1
Sample
y = 0,5538x
R2 = 0,9592
0,01
0,1
1
10
100
0,01 0,1 1 10 100
QEMSCAN Assay (%)
Ch
em
ical
Assay (
%)
Cu
Fe
Mo
S
Figure 1: QEMSCANTM and Direct Assay Reconciliation
Key QEMSCANTM mineralogical assays have been regressed with the chemical assays, as
presented in Figure 1. Overall correlation, as measured by R-squared criteria was 0,9592 with
a slope 0,5538. This is considered to be acceptable. Full QEMSCANTM and direct chemical
assays are presented in Appendix.
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3. Modal Analysis and Grain Size Distribution
A graphical summary of the particle modal analyses of the Andina project is presented in Figure
2. Full mineral distribution analyses of this sample are presented in Table 3.
The Comp Alim Ro sample is mainly composed by Quartz (35,68 wt.%), Sericite/Muscovite
(19,19 wt.%), K-Feldspar (18,45 wt.%), Plagioclase/Albite (8,98 wt.%) and with lower values
Tourmaline (4,16 wt.%), Pyrite (2,81 wt.%), Fe Oxides/Oxyhydroxides (2,57 wt.%), Biotite (1,41
wt.%), Clays (1,41 wt.%, mainly Kaolinite). With trace amounts there are Chlorite, Zircon,
Apatite, Ti Oxides, Carbonates (Calcite, Siderite mainly) and Gypsum/Anhydrite.
The ore minerals in sample are Chalcopyrite (2,50 wt.%), Enargite (0,05 wt.%) and Molybdenite
(0,03 wt.%).
4. Copper Occurrence
Cu distribution by grade is presented in Figure 3.
The main copper sulphide is Chalcopyrite which represents almost 97 % of the copper in
sample. Also, copper occurs as Enargite (2,50 %) and as trace there are Covellite and
Chalcocite/Digenite.
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Table 3: Modal Analysis and Grain Size Distribution
Survey Name Andina
Id 4320 - Q132
Sample Name Comp Alim Ro
Fraction Name -212/+3um
Mass Size Dist. (%) 100
Particle Size 88
Mineral Chalcopyrite 2,50
Mass Enargite 0,05
(%) Other Cu Sulphides 0,01
Pyrite 2,81
Molybdenite 0,03
Other Sulphides 0,01
Quartz 35,68
K-Feldspar 18,45
Plagioclase/Albite 8,98
Tourmaline 4,16
Amphiboles 0,07
Sericite/Muscovite 19,19
Clays 1,41
Biotite 1,41
Chlorites 0,77
Zircon 0,02
Fe Oxides/Oxyhydroxides 2,57
Ti Oxides 0,94
Carbonates 0,75
Gypsum-Anhydrite 0,05
Apatite 0,14
Other 0,01
Total 100,00
Mean Chalcopyrite 33
Grain Enargite 16
Size Other Cu Sulphides 6
(m) Pyrite 37
Molybdenite 14
Other Sulphides 8
Quartz 45
K-Feldspar 21
Plagioclase/Albite 26
Tourmaline 30
Amphiboles 8
Sericite/Muscovite 20
Clays 7
Biotite 11
Chlorites 13
Zircon 9
Fe Oxides/Oxyhydroxides 24
Ti Oxides 18
Carbonates 14
Gypsum-Anhydrite 22
Apatite 19
Other 8
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Figure 2: Bulk Modal Distribution
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Sample
Min
era
l M
as
s (
%)
Other 0,04
Apatite 0,14
Gypsum-Anhydrite 0,05
Carbonates 0,75
Fe-Ti Oxides 3,51
Phyllosilicates 22,79
Tourmaline 4,16
Feldspar/Amphibole 27,50
Quartz 35,68
Molybdenite 0,03
Pyrite 2,81
Other Cu Sulphides 0,05
Chalcopyrite 2,50
Comp Alim Ro
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Figure 3: Elemental Cu Deportment as CuT (left). Cu Distribution at 100% in Sample (right).
0,00
0,20
0,40
0,60
0,80
1,00
Sample
Cu
Gra
de I
n S
am
ple
(%
)
Chalcocite 0,00
Covellite 0,00
Enargite 0,02
Chalcopyrite 0,85
Comp Alim Ro0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Sample
No
rmali
zed
Cu
Gra
de i
n S
am
ple
(%
)
Chalcocite 0,18
Covellite 0,37
Enargite 2,50
Chalcopyrite 96,95
Comp Alim Ro
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5. Liberation
Liberation analyses in composites samples are presented in this chapter. For the purposes of
this analysis, particle liberation is defined based on 2D particle area percent. Particles are
classified in the following groups (in descending order) based on mineral area percent: free
(>=95%), liberated (=80%), middling (=50%), sub-middling (=20%) and locked ( 20% 8,40
Chalcopyrite Mid > 50% 5,37
Liberated Chalcopyrite > 80% 22,07
Free Chalcopyrite 49,82
Comp Alim Ro
Figure 4: Chalcopyrite Liberation in Samples
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Background
Chalcopyrite
Enargite
Other Cu Sulphides
Pyrite
Molybdenite
Other Sulphides
Quartz
K-Feldspar
Plagioclase/Albite
Tourmaline
Amphiboles
Sericite/Muscovite
Clays
Biotite
Chlorites
Zircon
Fe Oxides/Oxyhydroxides
Ti Oxides
Carbonates
Gypsum-Anhydrite
Apatite
Other
Figure 5: Image Grid of Chalcopyrite Liberation
5.2 Molybdenite Liberation
Molybdenite Liberation is presented in Figure 6.
Molybdenite is 49,94 % liberated and 44,39 % locked.
Figure 7 shows image grid of Molybdenite liberation.
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0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Sample
% M
oly
bd
en
ite M
ass In
Sam
ple
Molybdenite Locked 44,39
Molybdenite Sub-Mid > 20% 2,78
Molybdenite Mid > 50% 0,00
Liberated Molybdenite > 80% 49,94
Free Molybdenite 2,89
Comp Alim Ro
Figure 6: Molybdenite Liberation in Sample
Background
Chalcopyrite
Enargite
Other Cu Sulphides
Pyrite
Molybdenite
Other Sulphides
Quartz
K-Feldspar
Plagioclase/Albite
Tourmaline
Amphiboles
Sericite/Muscovite
Clays
Biotite
Chlorites
Zircon
Fe Oxides/Oxyhydroxides
Ti Oxides
Carbonates
Gypsum-Anhydrite
Apatite
Other
Figure 7: Image Grid of Molybdenite Liberation
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6 Associations
Association characteristics are summarized in this chapter.
For the purposes of this study:
All association classes are defined based upon particle area percent. Each binary
classification is defined as containing greater than or equal to (> or =) 95 area% of the
mineral in study (Chalcopyrite or Molybdenite, etc), plus the specified mineral or
mineral group.
Categories containing only a single mineral name represent only the mineral specified
(for example Pyrite).
The Other Copper Sulphides group is comprised of all copper sulphides, excluding the
mineral in study.
The Phyllosilicates category is comprised of clay minerals, micas and chlorites.
The Hard Silicates group is comprised of K-Feldspar, Plagioclase/Albite, Quartz,
Tourmaline...
The Hard Silicates/Phyllosilicates group represents the mineral in study in association
with a Hard Silicates and with a Phyllosilicates.
The Fe-Ti Oxides/Oxyhydroxides category is comprised of Fe Oxides
(Magnetite/Hematite) and Ti Oxides (Rutile, Ilmenite).
Particles containing the mineral in study which occurs with a combination of any of the
associations described above fall into the Complex association class.
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6.1 Chalcopyrite Association
Chalcopyrite association is showed in Figure 8.
Chalcopyrite is mainly associated with Phyllosilicates (17,83 %), Hard Silicates/Phyllosilicates
(9,61 %), Fe-Ti Oxides/Oxyhydroxides (5,62 %), Hard Silicates (4,07 %) and Pyrite (2,72 %).
Complex association reaches 9,69 %.
Examples of Chalcopyrite associations are showed in Figure 9.
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Sample
% C
halc
op
yri
te M
ass In
Sam
ple
Complex 9,69
Bin Chalcopyrite: Fe-Ti Ox./Oxyhydrox. 5,62
Bin Chalcopyrite: Hard Silicates/Phyllosilicates 9,61
Bin Chalcopyrite: Phylosillicates 17,83
Bin Chalcopyrite: Hard Silicates 4,07
Bin Chalcopyrite: Molybdenite 0,01
Bin Chalcopyrite: Others Cu Sulphides 0,64
Bin Chalcopyrite: Pyrite 2,72
Free Chalcopyrite 49,82
Comp Alim Ro
Figure 8: Chalcopyrite Association Distribution
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Figure 9: Image Grid of Chalcopyrite Associations
Examples of Chalcopyrite in association with Pyrite, Hard Silicates, Hard
Silicates/Phyllosilicates, Phyllosilicates and Fe-Ti Oxides/Oxyhydroxides are in Figures 10, 11,
12 and 13 respectively.
Figure 10: Examples of Chalcopyrite in association with Pyrite
Background
Chalcopyrite
Enargite
Other Cu Sulphides
Pyrite
Molybdenite
Other Sulphides
Quartz
K-Feldspar
Plagioclase/Albite
Tourmaline
Amphiboles
Sericite/Muscovite
Clays
Biotite
Chlorites
Zircon
Fe Oxides/Oxyhydroxides
Ti Oxides
Carbonates
Gypsum-Anhydrite
Apatite
Other
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Figure 11: Examples of Chalcopyrite in association with Hard Silicates
Figure 12: Examples of Chalcopyrite in association with A) Hard Silicates/Phyllosilicates and B) Phyllosilicates
Figure 13: Examples of Chalcopyrite in association with Fe-Ti Oxides/Oxyhydroxides
A
Background
Chalcopyrite
Enargite
Other Cu Sulphides
Pyrite
Molybdenite
Other Sulphides
Quartz
K-Feldspar
Plagioclase/Albite
Tourmaline
Amphiboles
Sericite/Muscovite
Clays
Biotite
Chlorites
Zircon
Fe Oxides/Oxyhydroxides
Ti Oxides
Carbonates
Gypsum-Anhydrite
Apatite
Other
B
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6.2 Molybdenite Association
Molybdenite association is showed in Figure 14.
Molybdenite in samples is mainly associated with Pyrite (49,44 %) and Hard Silicates (34,55 %),
specially Tourmaline and Quartz.
Examples of Molybdenite associations are in Figure 15.
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Sample
% M
oly
bd
en
ite M
ass In
Sam
ple
Complex 12,09
Bin Moly: Hard Silicates 34,55
Bin Moly: Chalcopyrite 0,53
Bin Moly: Pyrite 49,94
Free Moly 2,89
Comp Alim Ro
Figure 14: Molybdenite Association Distribution
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Background
Chalcopyrite
Enargite
Other Cu Sulphides
Pyrite
Molybdenite
Other Sulphides
Quartz
K-Feldspar
Plagioclase/Albite
Tourmaline
Amphiboles
Sericite/Muscovite
Clays
Biotite
Chlorites
Zircon
Fe Oxides/Oxyhydroxides
Ti Oxides
Carbonates
Gypsum-Anhydrite
Apatite
Other
Figure 15: Image Grid of Molybdenite Associations
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Summary of Results
The QEMSCANTM mineralogical study of Feed sample of the ore mineral from Andina project
identified the following characteristics:
The Comp Alim Ro sample is mainly composed by silicates as Quartz,
Sericite/Muscovite, K-Feldspar and Plagioclase/Albite. With lower amounts there are
Tourmaline, Pyrite, Fe Oxides/Oxyhydroxides, Biotite and Clays (mainly Kaolinite). Main
ore minerals are Chalcopyrite and Molybdenite.
Copper occurs mostly as Chalcopyrite (97 %) and in second place as Enargite (2,50 %).
As trace there are Covellite and Chalcocite/Digenite.
Chalcopyrite in sample is mainly free and it is mostly in association with Phyllosilicates,
Complex, Hard Silicates/Phyllosilicates, Hard Silicates and Pyrite.
Molybdenite is mainly associated with Pyrite and Hard Silicates (as Tourmaline and
Quartz).
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Appendix - QEMSCANTM Data
OL4320-Q132
Assay Reconciliation
y = 0,5538x
R2 = 0,9592
0,01
0,1
1
10
100
0,01 0,1 1 10 100
QEMSCAN Assay (%)
Ch
em
ica
l A
ssay (
%)
Cu
Fe
Mo
S
Sample QEM Chem QEM Chem QEM Chem QEM Chem
Comp Alim Ro 0,87 0,85 5,42 3,11 0,02 0,02 2,40 1,94
Assays (%)
SMoCu Fe