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PIOP Deposit Homogeneity
Graeme McDonald
January 2015
Executive Summary
Geochemical examples from the current resource models and metallurgical testwork have
demonstrated that there is a high degree of geological homogeneity between the different deposits
at the Pilbara Iron Ore Project (PIOP).
Background
In 2011, Graeme Campbell and Associates Pty Ltd were engaged to geochemically characterise the
proposed waste rock from three of the deposits of the PIOP (Campbell, 2011a). The deposits studied
were Delta, Champion and Eagle. Static testing was undertaken on material from Delta, Eagle and
Champion. Kinetic testing was only undertaken on material from Delta. Graeme Campbell and
Associates Pty Ltd also provided a Tailings Sample Testwork report on a single composite sample
obtained from the Delta deposit (Campbell 2011b). The results of these studies were incorporated
into the PIOP Pre‐feasibility Study (PFS) in 2012. One of the assumptions made as part of these
studies was that all of the deposits have similar geochemical characteristics; however this was not
demonstrated at the time.
This report will document examples of evidence supporting this assumption.
Geology
Within the Blacksmith tenement (M47/1451) there are five major valleys, or channels, incised into
the bedrock geology; Ajax, Blackjack, Champion, Delta and Eagle (Figure 1). Exploration by Flinders
has focussed on exploring these channel systems for Detrital Iron Deposits (DID), Channel Iron
Deposits (CID) and Bedded Iron Deposits (BID), both beneath and on the margins of the channels.
From the initial drilling in 2008 it became clear that the mineralisation present in all of these
deposits was considered to be the same. The physical and geochemical similarities are documented
and discussed in papers by McDonald (2011) and Petts et el (2011) and were presented at the 2011
Iron Ore Conference in Perth. This recognition resulted in defining a set of criteria that is used to
discriminate the different types of mineralisation across the whole project (Table 1). A schematic
cross section relevant to all deposits (Figure 2) also shows the relationship between the different
units.
Figure 1 – Location of the major deposits within the PIOP.
Table 1 – Criteria used to discriminate between the different types of mineralisation across the PIOP.
Strat Code Geology Fe % SiO2% Al2O3 % P % LOI %
Cover (RC) RC
Recent colluvium containing
BIF, Chert and Shale fragments
within a fine hematite matrix
30 to 40 30 to 50 2 to 10 0.03‐0.06 2 to 6
DID‐1
Fine hematite pisolites with
variable colluvium fragment
concentrations
30 to 50 20 to 35 4 to 12 0.02‐0.06 2 to 6
DID‐2Semi consolidated Pisolite
dominant45 to 55 10 to 20 2 to 10 0.03‐0.08 2 to 6
DID‐3
Semi consolidated Pisolite
dominant with hematite
fragments
55 to 65 3 to 10 1 to 8 0.03‐0.10 2 to 6
DID‐4
Competent hard hematite
fragments with hematite
matrix
58 to 65 1 to 6 1 to 4 0.05‐0.12 2 to 6
Channel Iron
Deposit (CID)CID
Goethite‐rich clays, goethite
oolites and pisolites and
including a basal conglomerate
40 to 62 3 to 7 1 to 12 0.04‐0.05 6 to 12
BIDgMassive and vuggy vitreous
goethite55 to 62 1 to 6 1 to 5 0.05‐0.16 8 to 12
BIDh
Weakly to moderately banded
with alternating hematite and
goethite bands
55 to 62 1 to 6 1 to 5 0.08‐0.20 5 to 10
Basement (BM) BMWeakly altered/mineralised to
fresh BIF, Chert and ShaleVariable depending on lithology
Detrital Iron
Deposit (DID)
Bedded Iron
Deposit (BID)
Typical Assay RangesResource Profile
Figure 2 – Schematic cross section of the PIOP mineralisation. Exaggerated vertical scale.
Resource Data
The physical and geochemical characteristics of the different geological units are used across all
deposits to guide the interpretation of the geological model that is used as the fundamental input
into the current PIOP Resource Estimate. Therefore, the current Resource Estimate provides an
excellent source of data that can be used to compare the geochemistry of the different deposits.
The current PIOP resource is 1,042 Mt @ 55.6% Fe, with 959.5 Mt of this on the Blacksmith
tenement (M47/1451). The Eagle, Delta and Champion deposits dominate the resource, contributing
almost 80% of the total (Table 2). All deposits have been modelled and estimated independently of
each other and therefore any homogeneity between deposits should be reflected in similar
geochemical signatures for a particular unit.
Deposit % of Blacksmith Resource
Eagle 30
Delta 27
Champion 21
Blackjack 9
Ajax 7
Paragon 4
Badger 1 Table 2 – The proportion of each deposit as a percentage of the total Blacksmith Resource.
Figure 3 shows a number of plots using the bulk geochemical signatures for each deposit taken
directly from the resource model. Each symbol represents a different geological unit and the
individual points within a unit represent data from different deposits. Despite some natural
variation, Figure 3 clearly shows that the geochemistry for a particular unit is unique and does not
vary greatly between deposits.
Figure 3 – Geochemical discrimination plots using data obtained from individual deposit resource models. Each
geological unit has its own geochemical signature that does not vary greatly between deposits.
Metallurgical Data
Metallurgical testwork at the PIOP has been ongoing since 2009. This work has been performed on
PQ sized diamond drill core obtained from all deposits with the exception of Ajax. Composite data
for individual geological units from each deposit is another source of information that can be used
for comparing different deposits. An example is discussed below.
Figure 4 shows the results of a trial where 26 composites that represent 4 different geological units
from across different deposits were scrubbed and wet screened with the sub 1mm fraction deslimed
at 45µm. For all 26 composites, regardless of geological unit or deposit, there was an increase in the
proportion of Fe, a larger decrease in the proportion of SiO2 and a decrease in the proportion of
Al2O3. Therefore, all units across all deposits are behaving in a similar way during this beneficiation
trial.
0.00
2.00
4.00
6.00
8.00
50.00 55.00 60.00 65.00
% Al2O3
% Fe
All Deposits ‐ Fe v Al
DID 1
DID 2
DID 3
DID 4
BID
CID
0.00
5.00
10.00
15.00
20.00
25.00
50.00 55.00 60.00 65.00
% SiO2
% Fe
All Deposits ‐ Fe v Si
DID 1
DID 2
DID 3
DID 4
BID
CID
0.00
2.00
4.00
6.00
8.00
10.00
12.00
50.00 55.00 60.00 65.00
% LOI
% Fe
All Deposits ‐ Fe v LOI
DID 1
DID 2
DID 3
DID 4
BID
CID
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
50.00 55.00 60.00 65.00
% S
% Fe
All Deposits ‐ Fe v S
DID 1
DID 2
DID 3
DID 4
BID
CID
Figure 4 –Similar results for scrubbing, wet screen and deslime trials for composites from various deposits.
Conclusion
The geochemical data from the resource models was used to demonstrate that there are similarities
between the different geological units from one deposit to another across a range of major
elements.
Metallurgical results have been used to show that different units from different deposits behave in a
similar fashion during beneficiation trials.
A number of examples from different sources have been used to demonstrate that there is a high
degree of homogeneity between the deposits at the PIOP. This conclusion could be applied to ore
and waste lithologies alike. Thus, supporting the assumptions made by Graeme Campbell and
Associates Pty Ltd in undertaking to geochemically characterise the proposed waste rock and tailings
of the PIOP.
Competent Persons
The information in this report that relates to Exploration Results or Mineral Resources is based on
information compiled by Dr Graeme McDonald who is a member of the Australian Institute of
Mining and Metallurgy and a full‐time employee of Flinders Mines Limited. Dr McDonald has
sufficient experience that is relevant to the styles of mineralisation and types of deposits under
consideration and to the activity which he is undertaking to qualify as a Competent Person as
defined in the 2012 Edition of the ‘Australasian Code for Reporting of Exploration Results, Mineral
Resources and Ore Reserves. Dr McDonald consents to the inclusion in the report of the matters
based on his information in the form and context in which it appears.
References
Campbell, G, 2011a. Flinders Pilbara Iron Ore Project (FPIOP): Geochemical Characterisation of Mine‐
Waste Samples from Delta, Eagle and Champion Pits – Implications for Mine‐Waste Management.
Campbell, G, 2011b. Flinders Pilbara Iron Ore Project (FPIOP): Geochemical Characterisation of
Process‐Tailings‐Solids Sample and Management Implications.
McDonald, G D, 2011. Geochemical Characterisation of Flinders Mines’ Pilbara Iron Mineralisation, in
Proceedings Iron Ore, pp 307‐313 (The Australasian Institute of Mining and Metallurgy: Melbourne).
Petts, A E, McDonald, G D and Corlis, N J, 2011. Channel and Detrital Iron Deposits of the Flinders
Mines Pilbara Iron Ore, in Proceedings Iron Ore, pp 125‐132 (The Australasian Institute of Mining
and Metallurgy: Melbourne).