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IGO LIMITED Audit Report / Information 2012

Oct 16, 2012

65111_rns_2012-10-16_4cb543a5-00b3-4490-bb74-82930dfa77f9.pdf

Audit Report / Information

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A S X R E L E A S E

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17 October 2012

Total Pages: 8

ASX Company Announcements Australian Securities Exchange Level 4, 20 Bridge Street SYDNEY NSW 2000

STOCKMAN PROJECT (100% IGO) MINERAL RESOURCES STATEMENT AS OF 30 JUNE 2012

HIGHLIGHTS

  • Global Mineral Resource: 13,986,000 Cu t @ 2.1% Cu, 4.3% Zn, 38 g/t Ag & 1.0 g/t Au

Independence Group NL (“IGO”) is pleased to announce new Mineral Resource estimates at the Stockman Project in Victoria, in accordance with the 2004 Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (the “JORC” Code 2004).

The Project was acquired by IGO via the off market takeover of Jabiru Metals Ltd in the June quarter of 2011. The Project is located in eastern Victoria, 300km north-east of Melbourne and encompasses two copper-zinc-silver-gold VMS (volcanogenic massive sulphide) deposits, Currawong and Wilga. During the year successful exploration has increased the Mineral Resources at both deposits to:

Currawong Deposit:

  • Mineral Resource: 10,329,000t @ 2.0% Cu, 4.0% Zn, 40 g/t Ag & 1.1 g/t Au

Wilga Deposit:

  • Mineral Resource: 3,657,000t @ 2.3% Cu, 4.9% Zn, 32 g/t Ag & 0.5 g/t Au

High Grade Resource Subset:

A feasibility study is being undertaken on the Currawong and Wilga deposits in conjunction with the State and Federal permitting processes. At the same time exploration is continuing proximal to the Currawong and Wilga deposits and regionally, across 130 square kilometres of the Company’s tenure.

Encouraging results from the Bigfoot prospect close to the Currawong deposit (see Figure 1) received during the year include 7.45m @ 0.7% Cu, 4.4% Zn, 153g/t Ag and 10.6g/t Au – down hole width. Big Foot mineralisation has not been included in the June 2012 Stockman Mineral Resource estimate and further evaluation has been planned after successful metallurgical testwork.

Suite 4, Level 5, South Shore Centre I 85 South Perth Esplanade i South Perth I Western Australia 6151 PO Box 496 I South Perth I Western Australia 6951 Telephone +61 8 9238 8300 I Facsimile + 61 8 9238 8399 Email [email protected] I Website www.igo.com.au

A S X R E L E A S E

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Figure 1: Stockman Project – Regional geology plan showing prospects of interest

Table 1: Stockman Copper-Zinc-Silver-Gold Project – June 2012 Global Mineral Resource Comparison

2012 Tonnes
Cu%
Zn%
Pb%
Ag ppm
Au ppm1
Currawong
Wilga
Indicated
9,548,000
2.0
4.2
0.8
42
1.2
Inferred
781,000
1.4
2.2
0.3
23
0.5
Sub Total
10,329,000
2.0
4.0
0.8
40
1.1
Indicated
2,987,000
2.0
4.8
0.5
31
0.5
Inferred
670,000
3.7
5.5
0.4
34
0.4
Sub Total
3,657,000
2.3
4.9
0.5
32
0.5
Total
13,986,000
2.1
4.3
0.7
38
1.0
2011 Tonnes
Cu%
Zn%
Pb%
Ag ppm
Au ppm1


Indicated
9,130,000
2.0
4.2
0.8
42
1.2
Inferred
305,000
1.4
4.1
0.6
34
0.5
Sub Total
9,435,000
2.0
4.2
0.8
42
1.2
Indicated
2,368,000
2.1
5.5
0.5
32
0.5
Inferred
887,000
3.0
2.9
0.2
23
0.2
Sub Total
3,255,000
2.4
4.8
0.4
30
0.4
Currawong
Wilga
Total
12,690,000
2.1
4.4
0.7
39
1.0

Notes to accompany Table 1 :

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A S X R E L E A S E

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  • 1 Au grades for Wilga are all inferred due to paucity of Au data in historic drilling.

  • 2 Resources include massive sulphide and stringer sulphide mineralisation. Massive sulphide resources are geologically defined, stringer sulphide resources are reported above a cut-off grade of 0.5% Cu or 2% Zn.

  • 3 Block modelling used ordinary kriging grade interpolation methods within wireframes for all elements and density.

  • 4 Refer to Table 3 for Mineral Resource estimation parameters.

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Figure 2: Stockman Cu-Zn-Ag-Au Project: Currawong Deposit - 3D isometric projection showing mineralised envelopes, drilling, planned development and down plunge mineralised

intersections.

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Figure 3: Stockman Cu-Zn-Ag-Au Project: Wilga Deposit - 3D isometric projection showing mineralised envelopes, drilling, planned development and down plunge mineralised intersections.

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A S X R E L E A S E

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Table 2: Stockman Copper-Zinc-Silver-Gold Project – June 2012 High Grade Mineral Resource Subset Comparison.

2012 HIGH GRADE SUBSET
Tonnes
Cu%
Zn%
Pb%
Ag ppm
Au ppm1
Currawong
Indicated
Wilga
Indicated
Inferred
High Cu (>1.2%)
4,997,000
3.0
4.2
0.8
43
1.2
High Zn (>3%)
2,043,000
0.9
6.5
1.1
48
1.5
Sub Total
7,040,000
2.4
4.9
0.9
44
1.3
High Cu (>1.2%)
995,000
3.0
6.5
0.6
36
0.7
High Zn (>3%)
838,000
0.8
7.4
0.6
36
0.5
Sub Total
1,833,000
2.0
6.9
0.6
36
0.6
High Cu (>1.2%)
317,000
6.4
6.2
0.5
39
0.5
High Zn (>3%)
171,000
1.0
8.2
0.6
37
0.5
Sub Total
488,000
4.5
6.9
0.5
38
0.5
Total
9,361,000
2.4
5.4
0.8
42
1.1
2011 HIGH GRADE SUBSET
Tonnes
Cu%
Zn%
Pb%
Ag ppm
Au ppm1
Currawong
Indicated
High Cu (>1.2%)
4,818,000
2.9
4.3
0.8
42
1.2
High Zn (>3%)
1,964,000
0.9
6.7
1.2
48
1.5
Sub Total
6,782,000
2.3
5.0
0.9
44
1.3
Wilga
Indicated
High Cu (>2%)
644,000
3.8
6.6
0.5
34
0.6
High Zn (>4%)
1,032,000
1.1
7.0
0.6
36
0.6
Sub Total
1,676,000
2.1
6.8
0.5
35
0.6
Inferred
High Cu (>2%)
191,000
8.3
5.4
0.3
38
0.4
High Zn (>4%)
117,000
1.3
7.6
0.5
33
0.5
Sub Total
308,000
5.6
6.2
0.4
36
0.4
Total
8,766,000
2.4
5.4
0.8
42
1.1

Notes to accompany Table 2 :

  • 1 Au grades for Wilga are all inferred due to paucity of Au data in historic drilling.

  • 2 Resources include massive sulphide and stringer sulphide mineralisation. Internal high grade domains are modelled and reported above cut-off grades of 1.2% Cu and 3% Zn.

  • 3 Block modelling used ordinary kriging grade interpolation methods within wireframes for all elements and density.

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A S X R E L E A S E

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Yours sincerely

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Chris Bonwick Managing Director Independence Group NL

COMPETENT PERSONS STATEMENT

Stockman Project Mineral Resource:

The information in this report that relates to the Stockman Mineral Resources is based on information compiled by Mr Bruce Kendall who is a member of the Australian Institute of Geoscientists and is a full-time employee of the Company. Mr Kendall has sufficient experience which is relevant to the style of mineralisation and type of deposit under consideration, and the activity which he is undertaking, to qualify as a Competent Person as defined in the 2004 edition of the JORC Code. Mr Kendall consents to the inclusion in the report of the matters based on his information in the form and context in which it appears.

COMPANY INFORMATION

BOARD OF DIRECTORS STOCK EXCHANGE LISTING Peter Bilbe Non-Executive Chairman Australian Stock Exchange Chris Bonwick Managing Director ASX 200 Code: IGO Kelly Ross Non-Executive Director Rod Marston Non-Executive Director John Christie Non-Executive Director CONTACT CAPITAL STRUCTURE Postal Address PO Box 496 Shares on Issue 232.9M South Perth WA 6951 Telephone: (08) 9238 8300 Email: [email protected] Website: www.igo.com.au

SHARE REGISTRY
Security Transfer Registrars Pty Ltd
770 Canning Highway
Applecross, WA 6153
Telephone:
(08) 9315-0933
Facsimile:
(08) 9315-2233
TOP 5 SHAREHOLDERS*
JP Morgan
22.58%
National Nominees
19.61%
HSBC Custody Nominees
18.36%
Citicorp Nominees
5.59%
BNP Paribas Nominees
3.69%
*as at 14 September 2012

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A S X R E L E A S E

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Table 3: Stockman Project – Currawong and Wilga Minera Resources Parameters

Geological setting Currawong and Wilga are V(H)MS style deposits, occurring as polymetallic (pyrite-sphalerite-
chalcopyrite) massive sulphide lenses within a volcano-sedimentary succession. Wilga is a single
stratabound lens whereas Currawong comprises multiple stratabound lenses with a series of faults
offsetting and stacking the lenses.
Drilling techniques All year 2010-2012 holes were diamond drilled from surface using a combination of HQ and NQ
core sizes. Historical holes were principally diamond drilling with the exception of several RC
precollars drilled by Denehurst and Austminex. None of the RC samples have been used in the
resource estimates. The surface diamond drilling is a mixture of HQ, NQ and BQ core sizes, with
BQ occurring only in the older WMC holes. The underground holes at Wilga were drilled LTK46 (Ø
= 35.6mm).
Drillhole Spacing Diamond drill coverage in the massive sulphide at Wilga and Currawong is on a nominal 25x25m
pattern. In the stringer sulphide lenses of both deposits, drillhole spacing ranges from 25x25m to
50x50m. Minimum hole spacing ~10m and maximum hole spacing ~70m. Some holes were
twinned in the 2008 drilling campaign and in 2012, one twin hole was completed (12WGDD030
was a twin of 12WGDD028).
Drillhole Collar
Positions
Most historic drillhole collar positions were surveyed by licensed or company surveyors. The
JML/IGO (2008-2012) drillhole collar positions were located using RTK GPS equipment with a
horizontal accuracy of +/-10mm and a vertical accuracy of +/-20mm. All resource work has been
conducted on local grids.
Drillhole directional
control
Dip and Azimuth readings – generally good quality surveys using downhole camera shots at about
30m intervals. Multi-shot surveys were introduced during the 2010/2011 drilling campaign with
downhole readings taken every 6m and these were continued through 2011/2012.
Geometry of
intercepts
Surface drilling intersects the massive sulphide lenses almost perpendicular to the lens orientation
at both Currawong and Wilga. The underground fan drilling at Wilga has some intercepts that are
almost dip parallel. Some sample bias will occur in the Wilga deposit due to this fan drilling
orientation but most of the affected area has already been mined and is excluded from the
resource estimate. Two down-plunge or down-dip holes were drilled at Currawong however these
were excluded from the estimate. They were drilled to detect offsetting faults, cross-cutting
intrusions and test the grade continuity along strike. In the resource estimate they were used
solely for geometry purposes. No down-plunge or down-dip holes were drilled at Wilga. Three of
the 2012 stringer drillholes at Wilga were drilled at low angles to the mineralisation due to the lack
of more appropriate drilling locations. These holes also do not represent a large volume of the
resource estimate.
Sampling techniques Mostly sawn half-core samples of NQ, BQ and LTK46, or quarter-core samples of HQ varying in
length up to 1.3m in the massive sulphide and adjusted to geological boundaries. Some quarter-
core NQ samples by Austminex where core was needed for metallurgical testwork. The 2010-
2012 drilling campaigns included a combination of sawn half-core NQ or quarter-core HQ, with a
typical sample length of 1m. A minimum sample length of 0.3m and maximum sample length 1.5m
in mineralised domains were adjusted to geological boundaries. All massive sulphide intercepts
have been sampled and sampling generally extends 10m into waste rock.
Data spacing and
distribution
The data spacing and distribution is more than sufficient to establish geological and grade
continuity appropriate for the Mineral Resource estimation procedure and classification applied.
Sample preparation
and assaying
All samples were crushed and a sub-sample pulverised followed by three or four acid digest with
AAS or ICP determination. All samples apart from the WMC samples were prepared and analysed
at independent laboratories. The assay techniques are for total digestion of the sulphides and are
considered appropriate for this type of mineralisation. For the 2010-2012 drill programs, all
samples were assayed at Genalysis Adelaide Laboratory using a 4 acid ore grade digest with an
ICP-OES finish. Au was assayed using a fire assay 50g charge and AAS determination. Lower
detection limits were to 50ppm for Cu, Pb, Zn, 1ppm/5ppm for Ag and 0.005ppm for Au.
Audits or reviews The Stockman database was rigorously checked during a data compilation and validation stage in
2008. Since then, routine validation of the database has been conducted in-house.

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Sample compositing 1m downhole composites with length and density weighting, face sampling at Wilga and recent
probe drillholes at Wilga were not used for grade interpolation nor were the down plunge holes at
Currawong.
Density Many samples had measured densities using either water immersion or air pycnometer
techniques. All IGO/JML samples were measured for density using water immersion techniques.
For those samples with no density measurement, a calculated density was applied to the sample.
The assays for Cu, Pb, Zn and Fe were compared with the measured densities and a second
power regression curve developed for each deposit. Densities were used in the sample
compositing.
Quality Control
procedures
In comparison with modern requirements, minimal quality control procedures were adopted by
companies completing the drilling programs before JML (eg. inclusion of only 17 field standards,
62 duplicates, 84 external laboratory checks in total). This shortfall was recognised by JML and
more rigorous check sampling programs were implemented. Quality control procedures in the
IGO/JML drilling programs included the insertion of standards, blanks, duplicates and cross-lab
checks. The check samples allowed detection of low order sample contamination at the laboratory
during the sample preparation stage and subsequent change in procedures for preparation of JML
samples (insertion of barren flushes between samples), along with a positive bias in Zn assays
using the four acid digest ICP/OES technique (up to 10% higher than anticipated Zn grades). This
technique was reviewed and changed to an alternate technique at Genalysis in 2010. The four
acid digest was altered to include the addition of bromide (method code 4AHBr) for Cu, Zn and Pb
with ICP/OES determination. Detection limits using the 4AHBr method with ICP/OES finish were
50ppm Cu, Zn and Pb. Samples returning values higher than 100ppm Ag using the original four
acid digest method (4AB/OES, detection limit 1ppm for Ag) were re-analysed using the 4AHBr
technique (detection limit 5ppm for Ag). Elements analysed are within acceptable limits. Results
from duplicate sampling indicate that stringer zone Cu has poor repeatability. Repeatability is
moderate to good for most other elements of interest. In 2011, IGO implemented sizing checks to
be completed at the laboratory on 10% of the samples submitted for assay.
Drill sample recovery Core sample recovery was good to excellent. Some lost core intervals have been recorded,
particularly where structures such as faults or underground workings (Wilga) were intersected by
the drilling. These intervals do not affect the resource estimate. One small area of poor sample
recovery at Wilga has been identified and isolated. This area corresponds with the presence of
chalcocite and has been classified as inferred. Core recoveries in new drilling are reviewed
regularly to ensure there are no new areas of poor sample recovery.
Geological logging
and photography
Holes were logged and photographed by the various companies completing the drilling programs.
JML/IGO core has been photographed both wet and dry. Geological logging is very thorough and
more than adequate for resource estimation. Logging has previously been on paper logs, which
were data entered and then loaded into the AcQuire database. Paper logs were scanned and
stored on the server. Over the last 3 years graphical paper logs have been generated but
geological logging has been digital via AcQuire data entry objects which were then uploaded
directly into the database. AcQuire data entry objects have in-built rules that allow for validation of
data as it is logged.
Geological
interpretation
Confidence in the geological interpretation for Wilga is high, with the mineralisation and geological
setting being simple and the availability of underground drilling, mapping and plans confirming the
interpretation. Currawong is more structurally complex and whilst confidence in the geological
interpretation is good, there is room for improvement with more drilling and further data review
required to firm up some of the structural detail. Both deposits have been modelled using the
massive sulphide as the main geological constraint. The main factors controlling continuity at
Currawong are a series of post-mineralisation faults which are interpreted as disrupting the lenses.
Dimensions Currawong (Main Lens) is about 300m long, 240m wide (down-dip), up to 35m thick and located
100-300m below surface. Wilga is about 400m long, 220m wide (down-dip), up to 35m thick and
located 50-150m below surface.

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Estimation and
modelling techniques
Ordinary kriging was used for grade estimation utilising Surpac v6.2 software. Search parameters
were based on variogram models for each element. Grade estimation was constrained to the
massive sulphide lens and stringer sulphide lens wireframes. At Wilga and Currawong, additional,
internal subdomains of high grade Cu and Zn (Cu>1.2%, Zn>3%) were included in the massive
sulphide lenses. Bulk density values were interpolated as for the other elements. No dilution was
included in the resource models for Wilga or Currawong this year. Grade estimation for Au at
Wilga may not be reliable due to a paucity of Au assays in the historic sample data. For this
reason the Wilga Au has been classified as Inferred.
Block modelling Currawong 10mX, 10mY, 10mZ parent cell size with subcelling to 1.25m in all directions. Wilga
10mX, 10mY, 5mZ parent cell size with subcelling to 1.25m in all directions.
Moisture Tonnages have been estimated using densities some of which were dry (those analysed at
external laboratories) and others that contained natural moisture. The natural moisture of the
Stockman massive sulphides is typically low (<0.5%).
Cut-off grades, top-cut
grades
No cut-off grades have been applied to the massive sulphide outer boundary but cut-off grades
were applied to help delineate the high grade Cu mineralisation (1.2%Cu) and the high grade Zn
mineralisation (3%) within the massive sulphide zones for both deposits. Cut-off grades were also
used to delineate the stringer mineralisation at both Wilga and Currawong. These cut-off grades
were 0.5% Cu or 2% Zn.
Mild top-cut grades have been used for elements where the Co-efficient of Variation was > 1.0.
The top-cut grades were determined from disintegration points on log probability plots.
(Currawong massive sulphide 8% Pb, 10g/t Au, no top-cut for Zn, Ag or Cu; Currawong stringer
sulphide 3% Pb, 13.9% Zn, 106g/t Ag, 10g/t Au, no top-cut for Cu; Wilga massive sulphide 26%
Cu, 4% Pb, 31% Zn, 110g/t Ag, 2.6g/t Au; Wilga stringer sulphide 15% Cu, 1% Pb, 11% Zn, 120g/t
Ag, 0.95g/t Au). A geological constraint (the massive sulphide zone) has been used as it is stable
and will not vary over time, unlike cut-off grades. Mineralisation within both the massive sulphide
and stringer lenses has been reported.
Mining and
metallurgical
assumptions
No assumptions about mining method, minimum mining width or internal mining dilution have been
made. Similarly, no assumptions about metallurgical treatment processes and parameters have
been made at this stage.
Previous mine
production
Wilga has been mined previously and the mining volume has been removed from the resource
estimate using the available void wireframes. The accuracy of these wireframes was checked
during 2012 after completion of an underground probe diamond drilling program.
Classification Classification was based on sample density and confidence in the geometry of the lenses. All of
the major massive sulphide lenses in both deposits were classified as Indicated. Stringer sulphide
was classified as Indicated or Inferred or sometimes left as Unclassified if there was limited
continuity across sections. Generally, where the sample density was 50x50m or less the resource
was classified as Indicated, where the spacing was greater than 50x50m the resource was
classified as Inferred. The Au grades at Wilga are considered Inferred due to a paucity of gold
assays in the historic drilling data.
Tenement and land
tenure status
Currawong and Wilga are located within MIN5523, a granted tenement held 100% by Stockman
Project Pty Ltd, which is a wholly owned subsidiary of IGO. There are no current Native Title
claims over the area but an agreement is in place with a previous claimant group that makes
provision for both the previous claimants and/or other indigenous groups who may assert an
interest in the future. The tenement is located on crown land administered by the Department of
Sustainability & Environment. The area is rugged and heavily forested with no significant heritage
sites identified. No significant impediments are believed to exist.
Audits or reviews An external review of the June 2012 resource estimate will be conducted during the second half of
2012.
Further work No additional resource drilling is planned at this stage of the project. Underground grade control
drilling will commence at both Wilga and Currawong once mine development begins.
Resource Model
numbers
CU_RSC_2012_07 and WG_RSC_2012_07

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