Tumpengan Tumpang Pitu

INTREPID MINES LIMITED

TUJUH BUKIT PROJECT
REPORT ON MINERAL RESOURCES,
LOCATED IN EAST JAVA,
INDONESIA

TECHNICAL REPORT

FOR
INTREPID MINES LIMITED
LEVEL 1, 490 UPPER EDWARD ST.
SPRING HILL, QLD 4004
AUSTRALIA

21 JUNE 2011

PHILLIP L. HELLMAN, BSC (HONS 1), DIP ED, PHD, MGSA, MAEG, FAIG

HELLMAN & SCHOFIELD PTY LTD TEL: +61 2 9858 3863

3/6 TRELAWNEY ST, EASTWOOD FAX: +61 2 9858 4077

NSW 2122 AUSTRALIA EMAIL: hellscho@hellscho.com.au

TUJUH BUKIT

2.0 CONTENTS
2.0 CONTENTS................................................................................................................................. 2
LIST OF FIGURES ...................................................................................................................................... 4
LIST OF TABLES ....................................................................................................................................... 6
LIST OF APPENDICES ............................................................................................................................... 6
3. SUMMARY .................................................................................................................................. 1
3.1 Property..................................................................................................................................... 1
3.2 Location .................................................................................................................................... 1
3.3 Ownership ................................................................................................................................. 1
3.4 Geology and Mineralization ..................................................................................................... 1
3.5 Exploration Concept ................................................................................................................. 1
3.6 Status of Exploration ................................................................................................................ 1
3.7 Development and Operations.................................................................................................... 2
3.8 Qualified Person’s Conclusions and Recommendations .......................................................... 2
4. INTRODUCTION ......................................................................................................................... 3
5. RELIANCE ON OTHER EXPERTS ............................................................................................... 4
6. PROPERTY DESCRIPTION AND LOCATION ............................................................................... 5
7. ACCESS, CLIMATE, LOCAL RESOURCES, INFRASTRUCTURE AND PHYSIOGRAPHY ............... 8
8. HISTORY .................................................................................................................................... 9
9. GEOLOGICAL SETTING ........................................................................................................... 11
9.1 Regional Geology ........................................................................................................................ 11
9.2 Local Geology ............................................................................................................................. 16
9.3 Deposit Geology .......................................................................................................................... 21
10. DEPOSIT TYPES....................................................................................................................... 39
11. MINERALIZATION..................................................................................................................... 39
11.1 Katak ..................................................................................................................................... 39
11.2 Gunung Manis ....................................................................................................................... 41
11.3 Candrian ................................................................................................................................ 42
11.4 Tumpangpitu ......................................................................................................................... 43
12. EXPLORATION ......................................................................................................................... 57
13. DRILLING ................................................................................................................................. 64
13.1 Drilling Contractor and Drilling Statistics .............................................................................. 66
13.2 Drilling Equipment .................................................................................................................. 66
13.3 Down hole Surveys ................................................................................................................. 67
13.4 Drill Hole Collar Survey and Topographic Survey ................................................................. 67
13.5 Summary Results of Drilling ................................................................................................... 67
14. SAMPLING METHOD AND APPROACH..................................................................................... 68
14.1 Core Processing Protocols ....................................................................................................... 69
14.2 Measurement of Specific Gravity............................................................................................ 71
14.3 Sampling Intervals................................................................................................................... 71
14.4 Core Recovery Data ................................................................................................................ 72
14.5 Comparison of Sludge Samples versus Core Samples ........................................................... 73
15. SAMPLE PREPARATION AND SECURITY ................................................................................. 75
15.1 Sample Splitting, Packaging and Labelling ............................................................................ 75
15.2 Procedures Employed to Ensure Sample Integrity ................................................................. 75
15.3 Use of IMN Employees in Sampling Procedure ..................................................................... 76
15.4 Sample Security and Transport ............................................................................................... 76
15.5 Analytical Laboratories ........................................................................................................... 77

HELLMAN AND SCHOFIELD | JUNE 2011

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15.6 Analytical Methods ................................................................................................................. 78
15.7 QAQC Procedures Employed ................................................................................................. 80
15.8 QAQC Results ........................................................................................................................ 83
16. DATA VERIFICATION ............................................................................................................... 84
17. ADJACENT PROPERTIES ......................................................................................................... 85
18. MINERAL PROCESSING AND METALLURGICAL TESTING ....................................................... 86
18.1 Sulfide Testwork ..................................................................................................................... 86
18.2 Summary of Oxide Testwork .................................................................................................. 86
18.3 Metcon Metallurgical Program ............................................................................................... 91
18.4 KCA Metallurgical Test Program ........................................................................................... 95
18.5 Ore and Waste Acid Neutralization Potential ......................................................................... 97
18.6 Future Work ............................................................................................................................ 97
18.7 Ore Processing ........................................................................................................................ 97
19. MINERAL RESOURCE AND MINERAL RESERVE ESTIMATE .................................................. 100
20. OTHER RELEVANT DATA AND INFORMATION....................................................................... 130
20.1 Porphyry Resource................................................................................................................ 130
20.2 Summary Of Preliminary Economic Assessment For The Tujuh Bukit Oxide Project ........ 135
21. INTERPRETATIONS AND CONCLUSIONS............................................................................... 144
21.1 Interpretations and Conclusion of the Porphyry Resource ................................................... 144
21.2 Interpretations and Conclusion of the Oxide Resource ........................................................ 144
22. RECOMMENDATIONS ............................................................................................................ 144
22.1 Recommendations for the Porphyry resource ....................................................................... 144
22.2 Recommendations for the Preliminary Economic Assessment of the Oxide Resource........ 145
23. REFERENCES ........................................................................................................................ 151
24. DATE AND SIGNATURE PAGE ............................................................................................... 153
25. ADDITIONAL REQUIREMENTS FOR TECHNICAL REPORTS ON DEVELOPMENT PROPERTIES
AND PRODUCTION PROPERTIES........................................................................................... 154
26. ILLUSTRATIONS .................................................................................................................... 154


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LIST OF FIGURES
Figure 1: Location of the Tujuh Bukit Project, Banyuwangi, East Java, Indonesia. .................................................................... 5
Figure 2: IUP Production Operation (outlined in red). ................................................................................................................. 6
Figure 3: IUP Exploration outlined in red. ................................................................................................................................... 6
Figure 4: Regional geology. ...................................................................................................................................................... 12
Figure 5: Location of the Tujuh Bukit project. ........................................................................................................................... 13
Figure 6 : Regional geology of the southeast corner of Java (Jawa Timur). .............................................................................. 15
Figure 7 : Distribution of mineral prospects ............................................................................................................................... 16
Figure 8 : Lithology of the Tumpangpitu prospect region ........................................................................................................... 17
Figure 9 : Lithology of the Tujuh Bukit project as mapped by Placer (2000-2001). ................................................................... 18
Figure 10 : Reduced-to-Pole magnetic image ........................................................................................................................... 20
Figure 11 : Lithology cross-section 11060 mN at Tumpangpitu ................................................................................................. 22
Figure 12 : Distribution of alteration styles at the Tumpangpitu prospect as mapped by GVM-Placer ...................................... 23
Figure 13 : Outcrop of crystal lithic tuff with possible fiame from the Salakan Prospect. ........................................................... 24
Figure 14 : Matrix-supported lithic-crystal tuff from hole GTD-34 (Zone A - Tumpangpitu) ....................................................... 25
Figure 15 : Nine locations where sediments are encountered at Tumpangpitu (Nov. 2010). .................................................... 26
Figure 16 : Images of sedimentary textures in fresh to incipiently propylitic-altered sediments ................................................ 28
Figure 17 : Interbedded, fine-grained volcanic sandstones (propylitic)...................................................................................... 28
Figure 18 : Images of laminated and banded sediment in drill hole GTD-10-162 ...................................................................... 29
Figure 19 : Very coarse grained tonalite (CT): GTD-09-42 (667m)............................................................................................ 32
Figure 20 : Mill breccia from an interpreted diatreme complex at Zone B.................................................................................. 34
Figure 21 : Clast of intense porphyry quartz vein stockwork ..................................................................................................... 35
Figure 22 : Left - Clast of quartz-magnetite alteration (potassic zone) ...................................................................................... 35
Figure 23 : Left - Clast of porphyry related Qtz-magnetite-pyrite altered rock ........................................................................... 35
Figure 24 : Left - Accretionary lapilli from GTD-09-60 ............................................................................................................... 36
Figure 25 : Charcoal wood fragments embedded within chlorite-clay altered mill (diatreme) .................................................... 36
Figure 26 : Muddy matrix breccias (GTD-09-107; 162.10m and 163m)..................................................................................... 37
Figure 27 : Cross-section 11220 mN at Tumpangpitu. .............................................................................................................. 38
Figure 28 : Plan of 5 planned drill holes that were subsequently drilled at Katak. ..................................................................... 40
Figure 29 : Plan of 5 planned drill holes that were subsequently drilled at Katak. ..................................................................... 40
Figure 30 : Alteration map at Gunung Manis ............................................................................................................................. 42
Figure 31 : Location of the Candrian porphyry prospect ............................................................................................................ 43
Figure 32 : Vuggy massive silica (vu-Hsi) alteration of lithic tuff ................................................................................................ 44
Figure 33 : Alteration section 11,200 mN (Placer grid) at Zone A.............................................................................................. 45
Figure 34 : Alteration section 10,910 mN (Placer grid) at Zone C, ............................................................................................ 46
Figure 35 : Alteration section 9045370 mN (UTM grid) at Zone B ............................................................................................. 47
Figure 36 : Plan of the principal porphyry Cu-Au-Mo intersections at Tumpangpitu (yellow bars), ........................................... 48
Figure 37 : Resource block model section 11040 mN (Placer grid) at Tumpangpitu. ................................................................ 49
Figure 38 : Alteration section 11040 mN (Placer grid) at Tumpangpitu (Nov. 2010). ................................................................ 50
Figure 39 : Top-left, GTD-10-167 (403m) Qtz-Mo (B-vein) with Py center-line. ........................................................................ 52
Figure 40 : Average grade of As in oxide drill holes for 3 oxidation classes (fresh, strong, complete) ...................................... 53
Figure 41 : Enrichment factor of As in oxide Zones A-F ............................................................................................................ 53
Figure 42 : Core from the porphyry zone in GTD-09-112 (731.20m depth). .............................................................................. 55
Figure 43 : Core from the porphyry zone in GTD-10-163 .......................................................................................................... 55
Figure 44: Distribution of Au anomalies in -80 mesh soil samples at Tumpangpitu, ................................................................ 60
Figure 45 : Distribution of Cu anomalies in -80 mesh soil samples at Tumpangpitu, ................................................................ 61
Figure 46 : Left – Aeromagnetic data flown by Golden Valley Mines (circa 1999) .................................................................... 63
Figure 47 : Distribution of drill holes at Tumpangpitu as of 9th May 2011. ................................................................................. 65
Figure 48 : Summary of core recovery for the diamond drilling programs at Tumpangpitu. ...................................................... 73
Figure 49 : Plots of Au in core and in corresponding sludge samples for Tumpangpitu. ........................................................... 74
Figure 50 : Plots of Cu in core and in corresponding sludge samples for Tumpangpitu. ........................................................... 74
Figure 51 : Contoured elevation model showing block model limits ........................................................................................ 100
Figure 52 : Location of new mineralised intercepts (red) ......................................................................................................... 101
Figure 53 : Example of sectional interpretation of Cu mineralised zone .................................................................................. 102
Figure 54 : Relationship of elevation to Cu mineralization shell and elevated Cu drill hole intercepts .................................... 102
Figure 55 : Deposit-wide cross section, Cu in 6m composites (transition and sulfide zone) ................................................... 106
Figure 56 : Deposit-wide long section, Cu in 6m composites (sulfide zone) ............................................................................ 107
Figure 57 : Deposit-wide cross section, Au in 6m composites (transition and sulfide zone).................................................... 108


TUJUH BUKIT

Figure 58 : Deposit-wide long section, Au in 6m composites (transition and sulfide zone) .................................................... 109
Figure 59 : Deposit-wide cross section, Mo in 6m composites (transition and sulfide zone) .................................................. 110
Figure 60 : Deposit-wide long section, Mo in 6m composites (transition and sulfide zone) .................................................... 111
Figure 61 : Deposit-wide cross section, As in 6m composites (transition and sulfide zone) ................................................... 112
Figure 62 : Deposit-wide long section, As in 6m composites (transition and sulfide zone) .................................................... 113
Figure 63 : Cu:Au relationship, 6m composites, sulfide mineralization ................................................................................... 113
Figure 64 : Cu:Mo relationship, 6m composites, sulfide mineralization .................................................................................. 114
Figure 65 : Cu:As relationship, 6m composites, sulfide mineralization ................................................................................... 114
Figure 66 : Au:As relationship, 6m composites, sulfide mineralization ................................................................................... 114
Figure 67 : Modelled variograms for Cu (from top: down hole, 040 and 130 directions, UTM) .............................................. 116
Figure 68 : Modelled down-hole variogram for Au .................................................................................................................. 117
Figure 69 : Modelled down-hole variogram for As .................................................................................................................. 117
Figure 70 : Modelled down-hole variogram for Mo ................................................................................................................. 117
Figure 71 : Location of resource in relation to Cu mineralization ............................................................................................ 118
Figure 72 : Location of Exploration Potential in relation to Inferred Resource ........................................................................ 121
Figure 73 : Combined drill holes and block model (oblique section) ....................................................................................... 122
Figure 74 : Legend for sections .............................................................................................................................................. 123
Figure 75 : Oblique section 3, drill hole GTD-08-42 and block model .................................................................................... 123
Figure 76 : Oblique section 6, drill holes and block model ...................................................................................................... 124
Figure 80 : Oblique section 10, drill holes and block model .................................................................................................... 126
Figure 81 : Location of oblique sections in relation to drill holes and block model ................................................................. 127
Figure 82 : Combined drill holes and block model (oblique section) -gold .............................................................................. 128
Figure 83 : Combined drill holes and block model (oblique section) - molybdenum ............................................................... 128
Figure 84 : Combined drill holes and block model (oblique section) - arsenic ........................................................................ 129
Figure 85 : Legend for composite sections for Au, Mo & As ................................................................................................... 129
Figure 86 : Oblique oxide section 9, new results from GTD-11-194 ....................................................................................... 131
Figure 87 : Oblique section 16, new results from GTD-11-201 ............................................................................................... 132
Figure 88 : Oblique section 18, new results from GTD-11-203 ............................................................................................... 133
Figure 89 : Oblique oxide section 6, new results from GTD-11-205 ....................................................................................... 134
Figure 90 : Oblique porphyry section 10, new results from GTD-11-206 ................................................................................ 135
Figure 91: Summary - Standard Bias Plot Lab: Intertek Method; FA30 Method: Au.............................................................. 162
Figure 92: Summary - Standard Bias Plot Lab: Intertek Method: GA02 Method: Cu ............................................................. 162
Figure 93: Charts for Standard: OREAS 53Pb Lab: Intertek ................................................................................................. 163
Figure 94: Check Assays - Au (FA30/Au-AA25); Cu (GA02/ME-OG62); Ag (GA02/ME-OG62)............................................ 165
Figure 95: Field Duplicate Charts (Au, Cu, Ag)...................................................................................................................... 166
Figure 96: Laboratory Repeatability Summary Report (Lab: Intertek) ................................................................................... 167


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LIST OF TABLES
Table 1 : Inferred Oxide Resource at Tumpangpitu as reported in January 2011 ..................................................................... 58
Table 2 : Number of core samples assayed per sampling interval (Tumpangpitu) .................................................................... 71
Table 3 : Summary of core recovery for the diamond drilling programs at Tumpangpitu .......................................................... 72
Table 4 : Method and detection limits for elements analysed in the Tumpangpitu drilling program. ......................................... 78
Table 5 : List of OREAS standards (CRM’s) used in the Tujuh Bukit Project ............................................................................ 82
Table 6 : List of OREAS standards (CRM’s) used in the Tujuh Bukit Project ............................................................................ 82
Table 7 : Summary Results of Metcon Test Program ................................................................................................................ 86
Table 8 : Summary of KCA Test Work ....................................................................................................................................... 88
Table 9 : Summary of KCA Column and Projected Field Recoveries ........................................................................................ 89
Table 10 : KCA Core Photograph Category Summary .............................................................................................................. 90
Table 11 : Metcon Composite Samples ..................................................................................................................................... 91
Table 12 : Head Assays ............................................................................................................................................................. 92
Table 13 : Comparison of Expected, Assayed, & Average Calculated Head Grades ................................................................ 92
Table 14 : Metcon Baseline Cyanidation Test Summary ........................................................................................................... 93
Table 15 : Effect of Higher Cyanide Concentration on Residue Grades .................................................................................... 94
Table 16 : Metcon Comminution Test Summary ........................................................................................................................ 94
Table 17 : Metcon Analyses of Final Leach Solutions ............................................................................................................... 95
Table 18 : Column Leach Test and Expected Field Recoveries ................................................................................................ 96
Table 19 : Cyanide Consumption ............................................................................................................................................... 97
Table 20 : Summary of assayed intervals within interpreted copper mineralised zone ........................................................... 103
Table 21 : Summary of 6m composites within interpreted copper mineralised zone (only sulfide intervals) ........................... 103
Table 22 : Summary of 6m composited densities within interpreted copper mineralised zone ............................................... 103
Table 23: Summary, by hole, of 6m composites within interpreted porphyry zone(sulfide intercepts only) ............................ 104
Table 24 : Block model extents ................................................................................................................................................ 118
Table 25 : Summary of Inferred Resources, sulfide zone ........................................................................................................ 119
Table 26: Production Statistics ............................................................................................................................................... 137
Table 27: Summary of Pre-Production Capital Costs ............................................................................................................. 139
Table 28 : Operating Costs ...................................................................................................................................................... 141
Table 29 : Summary of Financial Results ................................................................................................................................ 141
Table 30 : Internal Standards - Lab: Intertek; Method: FA30 ................................................................................................... 161
Table 31: Internal Standards - Lab: Intertek; Method: GA02 .................................................................................................. 161
Table 32: Internal Standards - Lab: Intertek; Method: GA30 .................................................................................................. 161
Table 33: Internal Blanks – Lab: Intertek ................................................................................................................................ 164
Table 34: Field Duplicates - ½ Core and Sludge samples ...................................................................................................... 165

LIST OF APPENDICES
Appendix 1. Details of drill hole locations

Appendix 2. QA/QC Report by D Lulofs


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3. SUMMARY
3.1 Property
The Tujuh Bukit Project comprises two exploration tenements (“IUPs”) covering a total area
of 11,621.45 hectares.

3.2 Location
The property is located approximately 205 kilometers southeast of Surabaya, the capital of
the province of East Java, Indonesia and 60 kilometers southwest of the regional center of
Banyuwangi. The property is centerd near 8° 35’ 20.6” S and 114° 01’ 08” N and is bound
within UTM co‐ordinates 163,000‐179,000 E and 9042000‐9055000 N.

3.3 Ownership
The IUP (Izin Usaha Pertambangan) ‐Explorasi and IUP Operasi and Produksi were granted to
PT. Indo Multi Niaga ("IMN") on 25th January 2010 by the Bupati of Banyuwangi (Regional
Administrator, Banyuwangi, East Java) under decree number 188/05/KP/429.012/2007.
Intrepid Mines Limited (“Intrepid”) and IMN have signed a Joint Venture agreement enabling
Intrepid to hold an 80% economic interest in the Tujuh Bukit Project.

3.4 Geology and Mineralization
The principal styles of mineralization that are the focus of exploration and delineation drilling
on the Tujuh Bukit Project are high‐sulfidation epithermal Cu‐Au‐Ag mineralization and
porphyry Cu‐Au mineralization. The rocks within the porphyry environment become
intensely altered by the passage of hot saline fluids of varying pH and by the late descent of
cool oxidized ground‐waters that are out of equilibrium with the host rocks.

These areas of rock alteration are typically zoned at the district‐scale, a feature that can
provide vectors to porphyry Cu‐Au ore in magmatic‐related hydrothermal systems. Porphyry
deposits contain the vast majority of the copper resources of the Pacific island arcs and
significant amounts of gold, silver and molybdenum. Porphyry copper‐gold deposits tend to
be large, fairly uniformly mineralized and relatively low‐grade deposits with great vertical
extent.

3.5 Exploration Concept
The project is of an advanced nature, with well understood geological potential and an
Inferred Resource. It will progress by infill drilling, step‐out drilling, drilling to depth and
follow‐up of geophysical (e.g. magnetic) and geochemical targets around the immediate area
of identified mineralization.

3.6 Status of Exploration
Resource delineation and step‐out drilling.


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3.7 Development and Operations
None as yet.

3.8 Qualified Person’s Conclusions and Recommendations
In the Qualified Person’s opinion, the character of the property is of sufficient merit to justify
continued drilling.


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4. INTRODUCTION
This technical report is prepared by P. L. Hellman, an Independent Consultant to Intrepid, to
comply with NI 43‐101 reporting guidelines. Technical information and data contained in the
report or used in its preparation are sourced from reports compiled by previous workers of
the property together with internal reports of the current tenement holders as well as the
authors own observations whilst visiting the site and working with data from the site
generated by others.

This report documents the second Inferred Resource estimate at the Tumpangpitu porphyry
Cu‐Au prospect in East Java, Indonesia. The Tumpangpitu Prospect forms a part of the
broader Tujuh Bukit Project. The objective of the report is to estimate the second Inferred
Mineral Resource and to assess the merits of continued drilling on the Prospect

The property has been visited by the Author on four occasions from November 2007. The
initial visit was focused on drilling programs at Tumpangpitu Prospects Zones C and A which
were aimed at defining oxide gold‐silver resources. These have been separately reported in
other NI 43‐101 reports (Hellman, 2008, 2009 & 2011). Later visits included reviews of drilling
on the deeper sulfide porphyry copper‐gold system. The Author observed the progress of the
drilling programs in the Zones C and A oxide areas, visited the site office at Pulau Merah and
provided advice on sampling, QA/QC, geological logging, geotechnical data acquisition and
general data handling protocols. The Author inspected the property over several days in
October 2010 and observed drilling activities, drill core and participate with on‐site
discussions with staff. The Author also inspected the property in December 2010 and
observed drill core handling in the Tumpangpitu core yard as well as attending meetings in
the site office at Pulau Merah.


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5. RELIANCE ON OTHER EXPERTS
The author of this report is an Independent Qualified Person and has relied on various
datasets and reports that were provided by Intrepid, and project consultants to support the
interpretation of exploration results discussed in this report on mineral resources. The data
that was provided to the author was deemed to be in good stead, and is considered to be
reliable. The author is not aware of any critical data that has been omitted so as to be
detrimental to the objectives of this report. There was sufficient data provided to enable
credible and well constrained interpretations to be made in respect of data.

Assay data is handled by an independent database bureau that receives electronic results
directly from the laboratory. The data is then directly transferred to the Author.

Statements regarding tenement status, legal right to mine and explore, environmental
liability have been accepted in good faith from Intrepid and are outside the expertise of
Hellman & Schofield Pty Ltd.


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6. PROPERTY DESCRIPTION AND LOCATION
The Tujuh Bukit Project comprises two adjoining IUPs (Izin Usaha Pertambangan) – an IUP
Exploration of 6623.45 hectares and an IUP Production Operation of 4998 hectares ‐ located
approximately 205 kilometers southeast of Surabaya, the capital of the province of East Java,
Indonesia and 60 kilometers southwest of the regional center of Banyuwangi. The Project is
centered near 8° 35’ 20.6” S and 114° 01’ 08” N and is bound within UTM co‐ordinates
163,000‐179,000 E and 9042000‐9055000 N. The tenements are located within the desa of
Sumberagung, Kecamatan Pesanggaran, Kabupaten Banyuwangi (Figure 1).

The IUP Exploration (Number – 188/9/KEP/429.011/2010) abuts and surrounds to the south,
west and north the IUP Production Operation. It was issued on 25 January 2010 for a period
of 4 years (Figure 2).The IUP Production Operation (Number – 188/10/KEP/429.011/2010)
was also issued on 25 January 2010 for a period of 20 years (Figure 2).The IUPs were issued in
compliance with the new Indonesian Mining Law (Law number 4 Year 2009) and concerning
the Extension Application and Adjustment of the pre‐existing KP Exploration to become an
IUP Exploration, and the KP Exploitation to become an IUP Production Operation.

The pre‐existing KP‐Explorasi (Kuasa Pertambangan or exploration mining permit) had been
granted to PT. Indo Multi Niaga on 16 February 2007 by the Bupati of Banyuwangi (Regional
Administrator, Banyuwangi, East Java) under decree number 188/05/KP/429.012/2007. This
followed directly from an initial SKIP tenure period and a subsequent one year period under
tenement license KP‐General Survey (decree No. 188/57/KP/429.012/2006 granted on 20
March, 2006).

Figure 1: Location of the Tujuh Bukit Project, Banyuwangi, East Java, Indonesia.


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Figure 2: IUP Production Operation (outlined in red).
(Green areas are generalised representations of areas of Protection Forest).

Figure 3: IUP Exploration outlined in red.
Green areas are generalised representations of areas of Protection Forest.


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Surface rights in the area are held by the Department of Forestry and include farmland,
production forests, protected forest areas, and some villages. The villages are located within
the IUP area but not in any of the areas identified for exploration at this point. The IUPs
require annual rent payments and submissions of quarterly reports regarding the company’s
activities on the tenement to the regional government.

The tenement boundaries were located with GPS coordinates and the boundary of the
tenements has subsequently been surveyed and marked with a concrete pegs.

The main mineralized prospect, Tumpangpitu, is located in the southeast portion of the
tenement and covers an area of about 3 by 2 kilometers. The other significant prospect,
Salakan, is located in the northwest part of the tenement and covers an area of about 6.0 by
4.0 kilometers. Other prospects at Gunung Manis, Katak and Candrian lie to the east of
Tumpangpitu. No historical mining activity has been conducted within or near to the
boundaries of the tenement.

Under the Terms of the Alliance Agreement, Intrepid was granted an option to acquire up to
an 80% economic interest in the Tujuh Bukit Project. The agreement recognizes the potential
to increase the area held under IUP up to a 25km radius from the existing IUP boundaries.

Intrepid has earned its 80% economic interest in the project through project funding of
A$5M (to earn 51%) and through funding further exploration for an additional A$3M to earn
an additional 29% stake.

Intrepid then free carries IMN's 20% towards completion of a Feasibility Study but this free
carry is limited to an additional A$42M. The Alliance Agreement includes payments to IMN
upon meeting various conditions.

Upon meeting conditions for the 80/20 economic interest, the parties then fund on a pro‐
rata basis equal to their percentage interest. Standard dilution clauses apply if either party
elects not to fund.

Intrepid advises that there is no knowledge of any environmental liabilities associated with
the project. A permit is required to conduct exploration activities within areas of protected
and production forest and these have been issued by the Department of Forestry for work on
this project.

This report is the fifth on mineral resource estimates from this prospect area within the
Tujuh Bukit Project.


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7. ACCESS, CLIMATE, LOCAL RESOURCES, INFRASTRUCTURE AND
PHYSIOGRAPHY
The project area encompasses Gunung Tumpangpitu (489 m ASL) and surrounding hill
country which graduates into alluvial plains near to sea level. The majority of landforms are
steep and rugged with poorly drained ephemeral streams having only seasonal discharges.
Streams and creeks on the northern side of Gunung Tumpangpitu drain into Sungai Gede
which flows actively for 8‐10 months of the year.

The region has a wet and dry season climate typical of tropical equatorial countries. The wet
season is subject to seasonal influence of the northwest monsoon from November to March.
Rainfall in the mountain ranges to the north ranges between 1725‐3500mm/year decreasing
toward the coast to 1110‐1850mm/year (Campbell, 2000). Temperatures range from 26‐31oC
during the day down to 22‐24oC overnight. Relative humidity is typically high, ranging from
80 to 100%. Whilst the agreeable climate allows exploration activity to continue year‐round,
prolonged dry weather may result in a lack of local water sources for drilling which then must
be sourced from Sungai Gonggo some 4‐6 kilometers to the east of Tumpangpitu.

On the lower slopes, government‐owned teak plantations, classified as Hutan Produksi
(Production Forest), are common and are administered by the Perhutani (Forestry
Department), Banyuwangi. Remnant stands of forest on the upper slopes and top of Gunung
Tumpangpitu are classified as Hutan Lindung (Protected Forest). Permits are required, and
have been issued, from the Perhutani for undertaking exploration within Protected and
Production Forest areas.

In lowland alluvial areas, or areas where tree plantations have been harvested, local farmers
grow cash crops such as corn, rice, coconut, bananas, chili, tobacco, vegetables and citrus.
The area also supports a small local fishing industry.

Road access to the project is afforded via sealed road from Surabaya (8 hours) and Denpasar,
Bali (7 hours). Roads are single lane and conditions vary from good to poor and are in a
constant state of repair. The trip from Bali includes a 1‐2 hour ferry crossing of the strait
between Bali and Java.

Helicopter access is available to the project from Bali. IMN has a helicopter on full time hire
at site and periodically uses the helicopter to transfer passengers to site. The flight takes
about 40 minutes.

Domestic and international flights operate daily to Surabaya and Denpasar from Jakarta,
Singapore and Australia.


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8. HISTORY
The project area was first explored by PT. Hakman Platina Metalindo and its JV partner,
Golden Valley Mines of Australia. Golden Valley Mines identified the potential of the
Tumpangpitu and Salakan areas as prospective targets for porphyry copper type
mineralization following a regional (1:50,000) drainage and rock‐chip geochemical sampling
program conducted during December 1997 – May 1998. Subsequently, a rapid detailed
surface geochemical sampling program was conducted over Gunung Tumpangpitu resulting
in seven targets being identified for drilling. An initial drilling program of 5 diamond drill
holes – GT‐001 to GT‐005 – was conducted during March – June 1999.

In February 2000 Placer Dome Inc. (Placer) entered into a Joint Venture with Golden Valley
Mines to earn 51% of the project and assumed operational control of the exploration
program. In order to better define targets for follow‐up drilling on Tumpangpitu 32.75
kilometers of grid‐based geochemical and IP surveys were completed between April‐May
2000. Anomalous bedrock geochemistry demonstrated marked consistency with prominent
ridges or topographic highs, trending to the northwest, consisting dominantly of vuggy silica
altered breccia.

The results of the IP survey demonstrated strong correlation between the near‐surface
resistivity anomalies and the outcropping vuggy silica zones. Deeper chargeability anomalies
(>200‐400 m below surface) were recorded in the northern portion of the grid. Placer
targeted the shallow resistivity anomalies for high sulfidation style Au‐Ag mineralization with
a further 10 diamond drill holes – GT‐006 to GT‐014.

On the basis of the results from the second drilling program a further 14 holes were designed
(2,700m). However, Placer withdrew from the project due to the combined influences of the
relatively low metal prices at the time (i.e., the project did not appear to meet corporate
thresholds of size and grade) together with an unstable economic and political climate across
much of south‐east Asia (the Asian Financial Crisis).

There is no report or record of further work being conducted on the project by Placer‐GVM
and the area became vacant by the time IMN applied for a KP General Survey in 2006 over
the project area.

In June 2006 Hellman and Schofield Pty Ltd (“H&S”, an independent geological consulting
group from Australia) assisted a previous Joint Venture of IMN with an Australian company in
assembling exploration data and designing a drilling program aimed at advancing the
Tumpangpitu prospect in order to report resource estimates according to the JORC Code and
Guidelines.

H&S was able to provide an indication of the size of potential mineralization within the
variably oxidized gold‐silver enriched zone above the deeper copper mineralization by using
the limited available drilling data along with soil sample geochemical results. This study


TUJUH BUKIT Page 10

suggested that approximately 3m oz Au Equivalent (“AuEq” was based on $650/Oz Au and
$10/Oz Ag) was a reasonable amalgamated target size in oxide Zones A, B & C.

Overall indications of potential may be expressed using cautionary language and with grade
and tonnage ranges. It should never be assumed that suggested grades and tonnages from
these types of studies will be realized, they are solely used in the context of understanding
the types of drilling targets and broad scale of mineralization.

On March 30, 2007 a Term Sheet was signed between Emperor Mines Ltd. (later to become
Intrepid. through the merger of Emperor Mines and Intrepid) and IMN and IndoAust Pty.
Ltd., which was followed by an Alliance Agreement between Emperor Mines Ltd, and IMN in
April 2008. Drilling on the project by IMN and Intrepid commenced in September 2007 with
hole GTD‐07‐015.

Additional historical drill hole assays became available between February and August 2007
enabling a slightly more informed view of the geological potential. The September 2007 H&S
study of Geological Potential used Ordinary Block Kriging of 2m composited AuEq data within
polygon extrusions.

This report documents the drilling completed by IMN and Intrepid during the period 2008‐
2011 on the porphyry copper‐gold mineralization.


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9. GEOLOGICAL SETTING

9.1 Regional Geology
The Tujuh Bukit project lies on the south coast of East Java, within the central portion of the
Sunda‐Banda magmatic arc which trends southeast from northern Sumatra to west Java then
eastward through east Java, Bali, Lombok, Sumbawa and Flores.

The Sunda‐Banda volcanic arc developed during subduction of the north‐moving Indo‐
Australian plate beneath the Asian continental plate margin. The Sunda‐Banda arc of Middle
Miocene to Pliocene age is thought to have initiated by subduction reversal following an
Oligocene compressive event that was associated with the northward emplacement of
ophiolite and island arc assemblages onto the Sunda margin and associated formation of
melanges, ophiolite fragments and deformation zones offshore from western Sumatra (Daly
et al., 1991; Harbury and Kallagher, 1991). The initiation of northward subduction beneath
the Sunda‐Banda arc migrated eastward following this collision event. The western segment
of the arc, west of central Java, developed on continental crust on the southern margin of
Sundaland whilst the arc east of Central Java developed on thinner island arc crust (Carlisle
and Mitchell, 1994).

There are substantial tectonic variations along the length of the Sunda‐Banda arc, and these
variations have been the subject of studies to understand along‐arc variations in magma
chemistry. Subduction is highly oblique along the northwest segment of the arc, along
Sumatra and towards the Andaman Islands and Burma (Moore et al., 1980). The strike‐slip
Sumatra Fault takes up much of the oblique convergence between the plates. Along this
northwest portion of the arc, very thick sedimentary sequences from the Bengal and Nicobar
fans are transported into the subduction zone. Further to the southeast, subduction is near
perpendicular to the Sunda‐Banda arc, off‐shore from Java, and only a very thin cover of
sediment enters the subduction zone. Further to the east, incipient areas of collision are
occurring along the arc where fragments of the Australian continental margin are accreting
against the Banda arc (e.g. Timor).

There are also variations in dominant styles of mineralization along the arc. In northern
Sumatra in the Aceh province, mineralization is characterized by porphyry Cu‐Mo systems
and high‐sulfidation deposits (e.g. Miwah and Martabe). In contrast, southern Sumatra, west
Java and central Java are typified by a lack of known porphyry systems but an abundance of
low‐sulfidation epithermal deposits or prospects/vein systems. Examples include Tambang
Sawah, Rawas, Lebong Donok, Lebong Simpang and Seung Kecil in southern Sumatra, plus
the Cikotok and Jampang districts, Gunung Pongkor and Cikondang in west Java and
Trenggallek in central Java. Further the east, in east Java and then through Lombok and
Sumbawa, there is a reappearance of porphyry and high‐sulfidation epithermal systems
along the eastern arc segment, including the Tumpangpitu high‐sulfidation epithermal and
porphyry system on Intrepid’s Tujuh Bukit project, The Selodong high‐sulfidation and


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porphyry district including the Motong Botek porphyry system on Lombok, and the Batu
Hijau porphyry Cu‐Au system on Sumbawa.

The Sunda‐Banda arc comprises both Miocene to Pliocene volcanics and younger Quaternary
volcanics. The arc has migrated not only from west to east over time but also from south to
north (Van Bemmelen, 1970; Whitford et. al., 1979; Katili 1989 and Claproth 1989). This
migration is clearly evident by the east‐west alignment of deeply dissected Miocene to
Pliocene volcanic centers along the south coast of Java, Lombok and Sumbawa and a parallel
east‐west alignment of juvenile and active Quaternary volcanoes that define the present
active arc further north along central Java and northern Bali, Lombok and Sumbawa (Figure
below).

Figure 4: Regional geology.

Relationship of the older, Miocene age, eroded volcanic centers (blue rings) that host mineralization at Trenggalek (low
sulfidation epithermal veins), Tujuh Bukit (high-sulfidation epithermal and porphyry system), Selodong (high-sulfidation
epithermal and porphyry system), and Batu Hijau (porphyry system), relative to the younger, Quaternary arc volcanoes to the
north which collectively make up the east-west trending present day Sunda-Banda arc.

The Sunda‐Banda arc is segmented by a series of arc‐normal structures that trend NNE and
which are evident in topographic data‐sets (Figure 4). Tectonic factors appear to have
localized volcanic centers of the Miocene arc at positions near the southwest margins of
these transfer structures. Contemporaneous continental to deep‐ocean clastic sediments
were deposited on the margins of the volcanic centers.


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The Tujuh Bukit project is located (Figure 5) near the southeast margin of a ~50‐km‐wide
annular zone of strongly dissected topography that is interpreted to represent the relics of a
former andesitic stratovolcanic center in East Java. This deeply dissected volcanic center
appears to be eroded to near its roots, close to the volcanic‐basement contact (Rohrlach and
Norris, 2006). Areas of similar topographic character occur along a WNW‐ESE linear zone that
also encapsulates an area in southern Sumbawa (which hosts the Pliocene‐age Batu Hijau
deposit ‐ 1640 mt @ 0.44% Cu, 0.55% Mo, 0.35 g/t Au; 3.7 Myr old (Figure 4).

Figure 5: Location of the Tujuh Bukit project.
It occurs on the southeast flank of a deeply incised Miocene-age volcanic center that is ~50 km in diameter (black dotted
outline).This eroded volcanic center lies SSW of the Quaternary volcano Gunung Raung which forms part of a larger
composite stratovolcano in east Java. Access to the Tujuh Bukit project area is by ferry from Gilimanuk (Bali) to Banyuwangi
(regional center of Jawa Timur – East Java), and then by road through Genteng and Jajag to the project site.

Figure 6 portrays the geology over an area of approximately 70 km x 25 km in southeast Java.
The broad stratigraphic succession of the area as defined on the 1:100,000 geology map of
the Blambangan Quadrangle is described below and comprises various formations of the
Lampon Group of Late Tertiary Age.

Batuampar Formation

The oldest rock in the area comprise the Batuampar Formation of Lower Miocene age. It
comprises a volcanic‐dominated succession of volcanic breccia (pyroclastic deposits), tuff,
sandstones and andesite lava with limestone intercalations. These rocks are described in the
regional 1:100,000 map as "being strongly altered", verified by Intrepid‐IMN field


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observations, since these rocks host mineralization at the Tumpangpitu prospect and at the
Salakan prospect. The volcanics of the Batuampar Formation comprise the roots of the
eroded volcanic structure depicted in Figure 5. Within the immediate environs of the
Tumpangpitu prospect the Batuampar Formation is dominated by intensely advanced argillic
altered coarse pyroclastic lithic tuffs and very subordinate (< 3%) limestone, marl and
volcanic sandstone. The limestone intercalations may become important as a source of lime
for mineral processing or control acid‐mine drainage in the future, as the Tumpangpitu
prospect progresses towards production stage.

Batuan Intrusives

Intrusive stocks of Middle Miocene age intrude the Batuampar Formation volcanic rocks and
are almost certainly responsible for the widespread alteration within that formation. They
are mapped on the 1:100,000 Blambangan Quadrangle as comprising porphyry andesite and
granodiorite, and are confined to the southeast corner of the Tujuh Bukit project area (Figure
6). Although these intrusives are not mapped in the Salakan prospect area on the 1:100,000
scale map, they are likely to lie at shallow depth below the prospect. Intrusive bodies have
been observed around the eastern periphery of the Salakan prospect by Intrepid‐IMN where
they are coincident with magnetic bodies. The magnetic tonalites intersected by the deep
drilling at Tumpangpitu are likely to be members of the Batuan Intrusive suite.

Jaten Formation

The Jaten Formation of Middle Miocene age comprises mixed sediments and tuffaceous
sediments (sandstone, conglomeratic sandstone, tuffaceous sandstone, calcareous
sandstone, claystone, tuff and tuffaceous limestone) which outcrop only in one mapped
locality, between the Batuampar Formation on the Capil promontory and the fault‐bound
sliver of Wuni Formation to the north.

Wuni Formation

The Wuni Formation is of Late Miocene to Pliocene age and comprises of breccia,
conglomerate, sandstone, tuff, marl and limestone. It outcrops only in two isolated localities
and is covered by extensive blankets of Quaternary marine sediment (limestones of the
Punung Formation) and transported Quaternary sediments of largely volcanic origin (Kalibaru
Formation) along the distal southern flanks of Gunung Raung.


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Figure 6 : Regional geology of the southeast corner of Java (Jawa Timur).

Punung Formation

The Punung Formation comprises a Quaternary sequence of reefal limestone, bedded
limestone and marl which forms a flat‐lying and recently emergent shallow marine
stratigraphic unit. The extensive exposure of Punung Formation limestones on the
Blambangan peninsula is likely contiguous with the isolated outlier of Punung Formation
exposed north of the Capil promontory. More restricted outcrops of limestone occur in the
Tujuh Bukit district in at least two localities.

Kalibaru Formation

The Kalibaru Formation comprises a Quaternary sequence of breccia, conglomerate, tuff and
tuffaceous sandstone which covers extensive areas on the eastern side of the Tujuh Bukit
property. The Kalibaru Formation appears to represent part of an extensive outwash sheet of
volcanic detritus that is largely derived from the Quaternary Mount Ruang composite
stratovolcano to the north. Near the Tujuh Bukit project, these Quaternary sediments lie
directly on the older Miocene‐age altered volcanic sequence of the Batuampar formation.


TUJUH BUKIT Page 16

9.2 Local Geology
Two areas of high topographic relief occur on the Tujuh Bukit property (Figure 7). The first of
these occurs on the southern‐most peninsula, coincident with the Tumpangpitu porphyry
and high‐sulfidation epithermal deposit, where extensive silicification associated with an
advanced argillic blanket overlies the Tumpangpitu porphyry system. This series of hills
extends to the east at lower elevation and cover the Katak porphyry prospect, the Candrian
porphyry prospect and the Gunung Manis low‐sulfidation epithermal prospect. The second
area of high topographic relief extends from the southern end of the western peninsula
northeast‐ward to the higher hills that are coincident with the Salakan prospect. Again,
extensive areas of silicification associated with advanced argillic alteration are responsible for
the erosional resistance of this elevated area at Salakan on the Tujuh Bukit property.

Figure 7 : Distribution of mineral prospects
Yellow outlines relative to topography mark various prospects. Numerous other exploration targets have been defined north
and east of Salakan based on interpretations of helibourne-acquired magnetic data (not plotted).

Understanding of the surface geology (lithology) of the Tujuh Bukit project area is quite
general in nature due to lack of detailed geological mapping over the entire region. This
understanding however is steadily growing as more detailed infill mapping is undertaken by


TUJUH BUKIT Page 17

Intrepid, and as interpretations of a regional magnetic dataset are progressively ground‐
truthed.

A lithology map over the Tumpangpitu area, and the hilly terrain east of Tumpangpitu, was
generated by PT Hakman Platina Metallindo prior to or during 1999 (Figure 8). This mapping
identified a dominantly diorite and microdiorite substrate which had been intruded by
extensive granodiorite bodies east of Tumpangpitu and by smaller quartz‐diorite bodies in
and around Tumpangpitu. These intrusions are considered equivalent to the Batuan
Intrusives described above. This map appears to be of “reasonable” accuracy given the
regional reconnaissance scale of the map, and known geology in and around Tumpangpitu.

Figure 8 : Lithology of the Tumpangpitu prospect region
In the area east of Tumpangpitu as mapped by PT. Hakman Platina Metalindo (1999). These mapped sequences comprise
volcanic breccias of the Batuampar Formation and more abundant Batuan Intrusives.

A complete lithology map also exists from the period of exploration by Placer (2000‐2001)
and is shown in Figure 9. This map shows similar geology to the map above, only with a more
restricted distribution of lithic tuffs mapped by Placer. In this respect, the PT Hakman map
(above) appears more correct than the Placer map. The Placer map however, also includes
lithology over the Salakan prospect area, where diorites are mapped intruding subvolcanic


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breccias, and with diorite intruded by quartz diorites. The extensive distribution of the
mapped breccia, however, suggests that it is more likely to be volcaniclastic in origin rather
than a subvolcanic breccia as labelled.

Figure 9 : Lithology of the Tujuh Bukit project as mapped by Placer (2000-2001).

Reasonably complete, though generalised, reconnaissance maps were subsequently
generated by IMN in 2006 over the Salakan and Tumpangpitu prospects. However, the PT
Hakman lithology map (Figure 8) is considered to be more reliable in the Tumpangpitu area.

Mapping subsequently undertaken by Intrepid (2009‐2010) covers three more local and non‐
contiguous areas:

1)   The coastline west of Tumpangpitu
2)   The Katak porphyry prospect, and
3)   The Gunung Manis low‐sulfidation epithermal prospect.

These local maps are of appropriate quality and detail to understand the geology in these
three areas. It is planned to progressively extend these maps to cover the entire region over
and east of Tumpangpitu. Consequently, both of the main prospect areas (Tumpangpitu and
Salakan) require significantly more detailed mapping to be undertaken.


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Due to limited mapping information, a significant portion of the geological understanding of
the regional lithology comes from drilling cross‐sections. The structural understanding of the
project area comes largely from interpretation of regional magnetic datasets.

The local to deposit‐scale lithology is discussed in Section 9.3 below whilst the deposit‐scale
alteration patterns are discussed in Section 11 (Mineralization) since alteration is intimately
related to mineralization events.

Within the broader area of the Tujuh Bukit project, an extensive volcanic‐dominated
succession of volcanic breccia (pyroclastic deposits), tuff, sandstones, and andesite lava with
limestone intercalations occurs, consistent with government map descriptions of this
volcano‐sedimentary sequence (Batuampar Formation).

In areas of low‐terrain, these sequences are overlain by Quaternary to recent alluvial
deposits, particularly around the Pancer coastal embayment south of Salakan and also
northwest and east of the Salakan hills.

The Batuampar Formation is intruded by numerous plutons and stocks that are identified in
all generations of regional mapping, in Intrepid/IMN drilling, and extensively identified in
magnetic data where they are recognized as magnetic features typical of I‐type calc‐alkaline
magmas. These are the Batuan Intrusives described above. Intrusive members recognized by
Intrepid include microdiorite, diorite, hornblende‐diorite, quartz‐hornblende‐diorite
hornblende andesite porphyry and tonalite. In addition to the mapped distribution of
intrusions, members of this suite have been identified south of Tumpangpitu and extensively
along the eastern periphery of Salakan. Several of these intrusives (either mapped or inferred
from magnetic data) are geochemically anomalous at surface.

Intense hydrothermal alteration has obscured a substantial portion of the original protolith
textures of many rocks in the district, particularly parts of the advanced argillic lithocap at
Tumpangpitu.

The structural framework of the Tujuh Bukit district is best interpreted using the heliborne
magnetic data‐set. Figure 10 shows a Reduced‐To‐Pole (RTP) magnetic image of the broader
Tumpangpitu Batholith and the East Salakan Batholith.

The aggregation of high‐amplitude magnetic anomalies within and around the eastern half of
the Salakan prospect are interpreted as Batuan intrusives, as are the linear array of magnetic
highs that trend northwest through the Tumpangpitu Batholith. The image is overlain by a
structural interpretation conducted by Chris Moore of Moore Geophysics. 1st order fault
corridors trend northwest, one passing near the northeast margin of the Tumpangpitu and
East Salakan batholiths, the other passing under Pancer Bay. A third sub‐parallel to low‐angle
northwest‐trending structure dissects the Tumpangpitu Batholith in approximately equal
halves. This fault structure localises a series of at least eight discreet magnetic high
anomalies over at least a 16 km structural strike length. These discrete magnetic anomalies
are interpreted as intrusive stocks emplaced along this structure. Consequently this district‐
scale structure was likely active during mid‐Miocene Batuan stage magmatism. This key


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regional fault (labelled “metallogentically fertile structure”) hosts the magnetic diorite
intrusion at the Katak porphyry system and the inferred magnetic intrusions immediately SSE
of the Gunung Manis low‐sulfidation epithermal vein array.

Figure 10 : Reduced-to-Pole magnetic image
This is broadly coincident with the eastern half of the Tujuh Bukit property. Black lines are interpreted regional faults. Blue
dashed lines envelope deep-seated batholiths, white outlines define structurally-controlled magnetic intrusive centers whilst
yellow outlines define a NW array of porphyry centers at Tumpangpitu. Details of this image are discussed in the text of the
report.


TUJUH BUKIT Page 21

The broader East Salakan Batholith and Tumpangpitu Batholiths are about 5 km in diameter.
At East Salakan, the batholith appears to be intruded in its core by a highly magnetic
intrusive about 1.5 km in diameter, and which is surrounded by a complex annual rim or zone
of magnetite destruction interspersed with small discrete magnetic highs (between the two
yellow outlines within the East Salakan Batholith). This magnetic pattern has the hallmarks of
a large hydrothermal system developed around the periphery of the intrusive core at East
Salakan.

Other 2nd order fault sets observed in the data shown in Figure 10 and trend ENE and WNW.

The overall geometry of these structures, forming braided to complex arrays of parallel and
curved, en echelon faults is reminiscent of major transcurrent fault systems.

Thus the district‐scale structural picture is of a regional NW‐trending structural corridor
which is likely to be a major crustal‐scale and near arc‐parallel strike‐slip fault zone. This
transcurrent fault system potentially guided the emplacement of the two large batholiths
beneath the eroded volcanic center. The erosional level within the Tujuh Bukit district is at
the right level to expose the top of porphyry systems whilst preserving the lower parts of
their respective epithermal environments, in other words, around the sub‐volcanic brittle‐
ductile transition. This opportune level of erosion has produced the complex magnetic
patterns characteristic of terrains that preserve the apical levels of multiple intrusive stocks
typical of the carapace of deep‐seated batholiths.

9.3 Deposit Geology
The Tumpangpitu deposit comprises a high‐sulfidation Cu‐Au‐Ag epithermal system that is
telescoped onto a large underlying and Au‐rich porphyry Cu‐Au‐Mo system.

In general terms, the overall mineralizing system broadly comprises a deep, magnetic
tonalite intrusion that has intruded into an older and more extensive feldspar‐hornblende
diorite stock. This older diorite intrusion has in turn intruded a cover sequence of lithic and
crystal‐lithic volcanic breccias that lie at shallow levels of the deposit. These volcaniclastic
tuffs and breccias conformably overlie a sequence of sediments that are ‘partly’ constrained
to dip inward towards the tonalitic intrusive center. The interface between the tonalite stock,
which is interpreted to be the progenitor of porphyry ore, and the overlying intrusive and
extrusive country rocks is characterized by the presence of one or more extensive diatreme
breccia bodies and numerous smaller hydrothermal breccias bodies. The upper portions of
the intensely altered and fluid metasomatised tonalite stock are transitional upward to
intrusive breccias (breccias with upward entrained interstitial melt) which in turn are
transitional at shallower levels to hydrothermal breccias as fluids have progressively exsolved
from the entrained and decompressing melt.


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Figure 11 : Lithology cross-section 11060 mN at Tumpangpitu
Deep porphyry holes (26, 29, 56, 112, 172, 182 and 192) are projected onto the 050-230° section.

The high‐sulfidation epithermal component of the Tumpangpitu mineralizing system can be
divided into four sub‐types based on oxidation intensity, metal grade and metal suite.

1) Completely oxidized high‐sulfidation ore (Au‐Ag strongly enriched; Cu severely
leached).
2) Partially oxidized high‐sulfidation mineralization (Au‐Ag +/‐ Cu; Cu is strongly
leached).
3)    Unoxidized but low‐grade high‐sulfidation mineralization (Au‐Ag‐Cu).
       Au‐Ag grade is significantly lower than the overlying oxide component.
4)    Unoxidized but higher‐grade high‐sulfidation mineralization (Au‐Ag‐Cu) in deeper
structural conduits and proximal to inferred upflow zones.

Components 3) and 4) only are reported for the current porphyry resource estimation,
however all four components of the high‐sulfidation mineralization are discussed in Section
11 of this report.

The geology of the Tumpangpitu prospect in the shallow epithermal environment is
dominated by intense hydrothermally altered (silica‐clay‐alunite‐pyrite) andesitic lithic
volcanic breccias, diatreme breccias, hydrothermal breecias and diorite, with the alteration
footprint covering an area in excess of 4 km x 2.5 km. The broader envelope of argillic altered
volcanics and intrusives are cross‐cut by several northwest‐trending and potentially


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structurally‐controlled zones of hydrothermal breccias which are advanced argillic altered
(vuggy silica, silica‐alunite, silica‐alunite‐clay, silica‐clay‐alunite and silica‐clay). These zones
of more siliceous alteration form multiple parallel ridges (2.5 km x 300 m) trending northwest
across the prospect (Figure 12), and they trend parallel to regional structures that are
evident in aeromagnetic imagery.

Figure 12 : Distribution of alteration styles at the Tumpangpitu prospect as mapped by GVM-Placer
Showing the locations of 14 historical drill holes (GVM – Holes 1 to 5 and Placer – Holes 6 to 14).

The geology of the deeper portions of the Tumpangpitu prospect is characterized by
alteration and vein assemblages characteristic of porphyry systems (Section 11). A large
tonalite intrusion is encountered in the lower parts of the deepest drill holes at
Tumpangpitu. This tonalite intrusion has a broad apex in the vicinity of cross‐sections
11040mN to 11360mN and plunges to greater depths to the SW and NE. The geometry of the
intrusion in detail is still being refined by infill drilling and magnetic modelling.

An interpreted diatreme breccia body (ovoid in plan and upward flaring) with a diameter of
approximately 500m occurs below the Zone C area of the oxide zone. This breccia is
dominated by polymict mill breccia in its middle and upper parts, and has roots that
penetrate down into the tonalite intrusions.  At deeper levels near the tonalite intrusion, the
breccia has increasing characteristics of an intrusion breccia. This breccia is a major feature
on two of the porphyry cross‐sections, and clasts of porphyry mineralization are incorporated
into the breccia (detailed descriptions provided in Section 9.3.4). Steeply‐oriented structural
feeders to high‐sulfidation mineralization have been intersected over‐printing this diatreme
breccia. Both these observations suggest that the timing of diatreme emplacement was
broadly syn‐mineral with respect to the porphyry system.


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Porphyry Cu‐Au‐Mo mineralization occurs within a carapace or shell of magnetite, quartz‐
magnetite and quartz vein stockwork that occurs within and around the periphery of the
causative tonalite intrusion, overprinting both the outer margins of the intrusion as well as
the proximal country rock. This mineralization occurs dominantly within areas characterized
by phyllic overprint of potassic alteration and lesser areas of potassic alteration within the
tonalite intrusion.


9.3.1 Volcaniclastic Breccias

Volcaniclastic breccias are a major rock type on the Tujuh Bukit project area (Figure 13 and
Figure 14). They comprise dominantly lithic tuff and crystal lithic tuff of andesitic (?)
composition, and are characteristically intensely argillic and advanced argillic altered. They
occur in the upper part of many oxide drill cross‐sections at Tumpangpitu, particularly in the
Zone A area which lies on the northeast side of the prospect, but are also observed occurring
widely around the eastern flank of the deposit,  as well as around the Katak porphyry system
2 km northeast of Tumpangpitu, where the breccias are intruded by the Katak diorite body.
Volcaniclastic breccias are also present around the northern and eastern fringes of the
Salakan prospect.

These volcaniclastic breccias are believed to be part of the Batuampar Formation described
above. The breccias tend to be heteorolithic in lithology and clast alteration intensity. The
volcanic breccias at Tumpangpitu are increasingly being viewed as part of an extensive and
large diatreme breccia complex that has poor internal layering.

Figure 13 : Outcrop of crystal lithic tuff with possible fiame from the Salakan Prospect.


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Figure 14 : Matrix-supported lithic-crystal tuff from hole GTD-34 (Zone A - Tumpangpitu)
This shows a strong alignment of flattened fiame-like pyroclasts. Sample from a zone of Hsi-cy alteration (silica-clay) with
clay-altered clasts and phenocrysts fragments, and silicified matrix.

In cross‐section, the breccias that occupy the Zone A hill (Gunung Tumpangpitu) were
previously interpreted as coarse lithic tuffs, but are currently interpreted as remnants of a
larger diatreme breccia body. Current interpretations have these massive units dipping
radially inward at a gentle angle towards the porphyry core. Crystal tuffs and broadly
conformable sediments mapped along the coastline west of Tumpangpitu dip gently to the
southeast, whilst other parts of the same sediment package further south along the coastline
dip to the northeast. On the Zone A oxide drill‐grid, the shallow lithic tuffs (currently re‐
interpreted on the two porphyry cross‐sections as diatreme breccias) are thought to dip
towards the southwest, based on the dips of concordant acid alteration zones. These
geometries collectively suggest a radially inward‐dipping series of volcanic ejecta. The
polymict nature of clasts in the lithic tuffs (or diatreme breccias) is consistent with a near‐
vent source. Two possible scenarios for this pattern can be considered:

Deflation of an underlying magma chamber causing structural subsidence above and around
the chamber.

Inward‐dipping blankets of volcanic ejecta developed around the inner rim of one or more
diatreme bodies within the region. If this is the case, these volcanic breccias must have
erupted onto the substrate rather than be intruded by it. The relationship between the old
diorite intrusion and the overlying volcaniclastic breccias continues to be investigated to
resolve the relative timing.

9.3.2   Sediments

A sedimentary sequence is widespread within the stratigraphic pile at Tumpangpitu (Figure
15), and occurs at RLs near and below sea‐level. The sedimentary sequence is likely to be a


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turbidite accumulation of sedimentary breccia, juvenile volcanic sandstone or wacke and
lesser mudstone, intercalated with rare marine limestone.

Figure 15 : Nine locations where sediments are encountered at Tumpangpitu (Nov. 2010).
Shapes are coastal outcrops whilst bars are subsurface drill-hole intersections of sediment units. Black and red dots show the
distribution of drilling at Tumpangpitu.

This sedimentary sequence is overlain by andesitic volcanics on the northeast side of
Tumpangpitu (Holes GTD‐08‐46 and GTD‐09‐94).

The sediments are interpreted to dip inward towards the porphyry center. Controls on dips
are reasonably well constrained on the southwest flank of the porphyry system, but are
poorly constrained on the northeast flank of the system. It is postulated that the inward dip
of these sediments is related to the geometry of a diatreme‐related porphyry system.
Geometric similarities are tentatively being made by B. Rohrlach (Intrepid chief geologist)
with the Marcapunta deposit in central Peru, where a diatreme and dome complex is rooted
above a porphyry system, with 400‐500m inward subsidence of sediments within the host
stratigraphic pile.

The sedimentary sequence at Tumpangpitu shows increasing degrees of metasomatism
(hydrothermal alteration) and veining as the sediments approach the porphyry center. The
degree of hydrothermal overprint observed in these sediments range from near fresh (Area 1
coastline and GTD‐08‐26), to propylitic altered and fractured (GTD‐08‐28), to intermediate


TUJUH BUKIT Page 27

argillic and argillic altered (GTD‐09‐94), and subsequently to strong advanced‐argillic and
phyllic alteration (GTD‐08‐46 and GTD‐08‐42), often with intense overprinting stockwork.

Areas of the sedimentary sequence that occur in close proximity to the main Tumpangpitu
tonalite body are intensely disrupted by cross‐cutting intrusive breccias, microdiorite and
tonalite bodies (potential dykes). The occurrences of these features in the sediment
sequence indicate close proximity to the main tonalite porphyry body.

The sediments, and in particular the calcareous and carbonaceous component of these
sediments, show increasing signs of sulfidation and incipient skarn development as the
tonalite porphyry body is approached, as evidence by:

 Intense sulfidation (pyrite) in mudstone horizons, with anomalous Cu, Au and Zn in sulfidized
sediment (GTD‐08‐26).

 Garnet alteration of sediment with anomalous Zn reflecting incipient calcic exoskarn
assemblages (GTD‐09‐94).

 Garnet and vesuvianite alteration (skarn assemblage) in local carbonate units within the
sedimentary package (GTD‐08‐46).

 Incipient magnetite skarn type replacement of sediments, grossly concordant to bedding at
the scale of drill core (GTD‐08‐42).

The collective observations above suggest increasing degrees of contact metamorphism and
skarn development within reactive (non‐siliciclastic) units of the sediment package, in close
proximity to the Tumpangpitu tonalite.

Clasts derived from the surrounding sediment host sequence are incorporated into some of
the major diatreme breccia bodies, particularly in GTD‐08‐29 where the mudstone
component of the sediments is intensely brecciated, with clasts of sediment incorporated
into the cross‐cutting diatreme breccia. Various examples are provided in Figure 16 to Figure
18.



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Figure 16 : Images of sedimentary textures in fresh to incipiently propylitic-altered sediments
From drill hole GTD-08-26, southwest of Zone C.

Figure 17 : Interbedded, fine-grained volcanic sandstones (propylitic)
Includes recessively weathered tuffaceous? siltstone (Locality 2). Thicknesses of individual beds are similar to those in the
type section in drill hole GTD-08-26 where the sediments have a turbidite appearance.


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Figure 18 : Images of laminated and banded sediment in drill hole GTD-10-162
The sediments here are much more strongly metasomatized than in GTD-08-26 where they are almost unaltered.
Nevertheless, textural similarities can be seen that identify these rocks in GTD-10-162 as sediments, namely centimetre-
scale banding, finer laminations, and local preservation of cross-bedding textures. The sediments are overprinted by sparse
networks of Fe-carbonate veins, potentially akin to those calcite veins observed in GTD-08-26.

9.3.3 Intrusives

The geology of Tumpangpitu deposit consists of a multiple intrusion complex with members
that vary in composition (diorite to tonalite), in texture (equigranular to porphyritic) and in
size (small dykes to stocks). The intrusive rocks observed to date in chronological order
include coarse‐grained diorite (CD), fine‐grained Tonalite (FT), coarse‐grained Tonalite (CT),


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