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Resource Evaluations Pty Ltd Level 1, 83 Havelock Street, West Perth 6005

Ph: 08 9226 3866 Fax: 08 9226 3877

Mineral Resource Estimate and Procedures Review

Anjing Hitam Zn-Pb-Ag Deposit,

Dairi Project, Sumatra, Indonesia.

Gerry Fahey MAusIMM (CP) MAIG

October 2004

Prepared for PT Dairi Prima Mineral

Gedung Bank Syariah Mandiri

JL. Sultan Husanuddin No. 57 Lantai 4

Kebayoran Baru, Jakarta Selatan, Indonesia, 12160

EXECUTIVE SUMMARY .................................................................................................................... 1 1.0 INTRODUCTION...................................................................................................................4

1.1 Scope of Work...................................................................................................................... 4 1.2 Project Location and Access................................................................................................ 4 1.3 Data Supplied....................................................................................................................... 4

2.0 GEOLOGY AND MINERALISATION.................................................................................... 6 2.1 Regional Setting .................................................................................................................. 6 2.2 Project Geology, Structure and Mineralisation .................................................................... 6

3.0 EXPLORATION HISTORY.................................................................................................... 7 3.1 Discovery.............................................................................................................................. 7

4.0 DATA COLLECTION AND PROCEDURES.......................................................................10 4.1 Introduction.........................................................................................................................10 4.2 Diamond Drilling .................................................................................................................10 4.3 Surveying............................................................................................................................11

4.3.1 Grid Control.................................................................................................................11 4.3.2 Collar Surveys.............................................................................................................12 4.3.3 Downhole Surveying...................................................................................................12

4.4 Core Handling, Photography and Storage.........................................................................13 4.5 Logging...............................................................................................................................14 4.6 Core Sampling....................................................................................................................15 4.7 Mapping..............................................................................................................................15 4.8 Sample Preparation............................................................................................................15 4.9 Geochemical Analysis........................................................................................................17 4.10 Bulk Density Data ...........................................................................................................17 4.11 Quality Control ................................................................................................................17

5.0 DATABASE DEVELOPMENT AND VALIDATION.............................................................21 5.1 Introduction.........................................................................................................................21 5.2 Collar and Downhole Survey Data.....................................................................................21 5.3 Assay Data .........................................................................................................................22

6.0 GEOLOGICAL MODELLING ..............................................................................................22 6.1 Introduction.........................................................................................................................22 6.2 Preparation of Wireframes .................................................................................................22

7.0 STATISTICAL ANALYSIS...................................................................................................24 7.1 Introduction.........................................................................................................................24 7.2 Sample Length Analysis.....................................................................................................24 7.3 Compositing and Data Coding...........................................................................................25 7.4 Descriptive Statistics and Application of Cut-off Grades ...................................................25

8.0 VARIOGRAPHY STUDY.....................................................................................................26 8.1 Methodology.......................................................................................................................26

2

8.2 Model Variography .............................................................................................................26 9.0 BLOCK MODEL DEVELOPMENT......................................................................................28

9.1 Introduction.........................................................................................................................28 9.2 Block Model Extents and Block Size..................................................................................28 9.3 Density Assignments..........................................................................................................29 9.4 Block Model Validation.......................................................................................................30

10.0 GRADE ESTIMATION.........................................................................................................32 10.1 Introduction .....................................................................................................................32 10.2 Ordinary Kriging..............................................................................................................32 10.3 Validation of Estimates ...................................................................................................34

11.0 RESOURCE REPORTING .................................................................................................35 11.1 Resource Classification..................................................................................................35

12.0 CONCLUSIONS AND RECOMMENDATIONS..................................................................37 13.0 REFERENCES ....................................................................................................................38 14.0 APPENDICES......................................................................................................................39

EXECUTIVE SUMMARY Resource Evaluations (ResEval) was commissioned by Herald Resources Ltd (Herald) on behalf of PT Dairi Prima Mineral to conduct a review of drilling, sampling and assaying procedures in May 2004 and carry out mineral resource estimates in June and August 2004 for the Anjing Hitam Zn-Pb-Ag deposit. The deposit is located within the Generation VII Dairi Contract of Work (CoW) in North Sumatra, Indonesia, 120km south southwest of the provincial capital Medan and 3km south of the village of Sopokomil. PT Dairi Prima Mineral is the current owner of the Dairi CoW which is a joint venture between Herald (80%) and PT Aneka Tambang (Persero) of Indonesia (20%). The deposit was discovered by Herald in 1997. The review and estimation process included: • A site visit to examine drilling and sampling procedures and contract sample

preparation and assay laboratory procedures. • The incorporation of major lithostratigraphical and structural features within the

deposit. • Resource estimation for Zn, Pb, Ag and Zn_Eq (zinc equivalent). The ResEval Mineral Resource estimate is summarised in Table 1.

Resource Summary – Anjing Hitam Deposit August 2004 Mineral Resource

Undiluted Mineral Resource 5% Zinc Equivalent Cut-off

Category Zone M Tonnes Zn % Pb % Ag g/t Zn_Eq % Measured MMH 5.4 16.5 10.2 13 24.7 Indicated MMH 1.8 14.3 8.5 11 21.1 Indicated Minor 0.5 16.3 9.5 13 23.8

Total Measured + Indicated 7.7 16.0 9.8 12 23.8 Inferred Minor 0.3 10.3 5.4 11 14.6

Total Inferred 0.3 10.3 5.4 11 14.6 TOTAL 8.0 15.8 9.6 12 23.5

Table1. Anjing Hitam August 2004 Mineral Resource Summary

Note: The ResEval August 2004 mineral resource estimate was carried out using 3-D wireframes created in Surpac software and interpolated using Datamine software.

The mineral resource estimate complies with recommendations in the Australasian Code for Reporting of Mineral Resources and Ore Reserves prepared in 1999 by the Joint Ore Reserves Committee (JORC). It is therefore suitable for public reporting. The drilling, sampling and assaying procedures comply with industry standards and are appropriate for use in the Bankable Feasibility Study (BFS).

The mineral resource estimate was completed using the following parameters: • The Anjing Hitam resource area extends over a strike length of 720m (from

9,440mN to 10,160mN) and includes the 300m interval from 830mRL to -530mRL.

• Drill holes used in the estimate included 103 diamond core holes for 24,189.7m.

• Holes in the Anjing Hitam area were drilled at spacings of 50m x 50m and 50m x 30m.

• Core was either triple tube HQ or NQ size. The core was sampled by cutting half core at intervals up to 1m and was sampled to geological boundaries.

• Samples were sent to Intertek Testing Services (ITS) sample preparation facility

in Medan. Following preparation, pulp samples were sent to the ITS laboratory in Jakarta where the samples were subjected to a screening analysis for Ag, Cu, Pb and Zn by AAS geochemical analysis using a perchloric/hydrochloric acid digest.

• Quality control data was available. Results were reviewed by ResEval and were

satisfactory. • Drillhole collars have been accurately surveyed in UTM grid. • Downhole surveys were carried out on all holes using an Eastman single shot

camera. • Wireframes were constructed using cross sectional interpretations based on

mineralised envelopes constructed at a nominal 5% zinc equivalent cut-off grade. Samples within the wireframes were composited to even 1.0m intervals.

• The zinc equivalent used was: Zn assay + 0.8 x Pb assay. This is based on long

term metal prices of $US1050/t for zinc and $US650/t for lead and differential “typical” smelter payments and charges.

• A block model was created for the estimate having block size of 10m EW x 20m

NS x 2m vertical with sub-cells of 2.5m x 5m x 0.5m. • Ordinary kriging (OK) was selected for grade interpolation to incorporate deposit

variography into the model. Kriging was only attempted on the Main Mineralised Horizon (MMH) due to the small number of samples in the minor zones, hence restricting variography for these zones. The minor zones were estimated using inverse distance squared (ID2) grade interpolation. The results of the variography generally matched the interpreted geology and geometry of the MMH with an overall northerly strike and moderate easterly dip to the mineralisation. The low nugget and long ranges evident in the variograms confirm the excellent continuity of grade which was observed in the drilling data.

• The short range structures in the main axis for Zn and Pb were both 75m, which

is greater than the typical drill hole spacing and suggests that the drilling should have defined the grade of the deposit with a high degree of confidence.

• The ID2 grade interpolation used a search ellipse with a first pass radius of 60m,

a second pass radius of 120m and a third pass radius of 300m, with the ellipse oriented to match the overall dip and strike of the mineralised zones.

• Bulk density data was measured for the majority of sample intervals in this

resource. These values were used to interpolate density values into the block model.

• Resource classification was carried out on the basis of continuity of

mineralisation and drill hole spacing. The mineral resource was largely classified as Measured and Indicated due to the excellent continuity of the MMH and the adequate drillhole spacing for this style of deposit. Some of the upper lenses were also classified as Indicated where there was sufficient drilling to identify a continuous horizon. Peripheral zones of mineralisation were classed as Inferred due to the lack of continuity, the small number of drill intersections and/or the reduced confidence of structure.

The estimate was completed under the overall supervision and direction of Gerry Fahey who is a Competent Person as defined by the Australasian Code for the Reporting of Mineral Resources and Ore Reserves (JORC Code) 1999 Edition and who consents to the inclusion in this report of the matters based on his information in the form and context in which it appears. The team of people involved in the preparation of this report are listed as follows: • Mr A Green (ResEval Consultant) responsible for interpretation, digitising,

wireframe construction, statistical analysis and Mineral Resource estimation.

• Mr P Payne (ResEval Principal) responsible for the statistical analysis and Ordinary Kriging estimation (June 2004 estimate).

• Dr N Reynolds (CSA Consultants) responsible for geological interpretation. • Mr L Widenbar (Widenbar and Associates) responsible for the statistical analysis

and Ordinary Kriging estimation (August 2004 estimate). • Mr G Fahey (ResEval Principal) responsible for overall due diligence and

resource classification.

1.0 INTRODUCTION

1.1 Scope of Work Resource Evaluations Pty Ltd (ResEval) was commissioned by Mr T.W. Middleton, International Exploration Manager of Herald Resources Ltd (Herald) to undertake a review of drilling, logging, sampling and assaying procedures at the Anjing Hitam Zn-Pb deposit and carry out a mineral resource estimate. During the period 18th – 25th May 2004, Gerry Fahey of ResEval conducted a review of drilling, logging and surveying procedures on site at Anjing Hitam, inspected the Pt Intertek Utama Services (ITS) sample preparation facilities at Medan in Sumatra and reviewed the geochemical analysis procedures at the ITS laboratory in Jakarta. The conclusion from the site visit is that all procedures have been carried out to acceptable industry standards. A structurally focused geological assessment of the deposit was carried out by Dr Neal Reynolds of CSA Australia Pty Ltd (CSA) which provided the basis for an updated sectional interpretation of the resource based on the 2004 infill and extension drill programme. This study was then used to develop a 3-D geological and resource model created by ResEval as part of the Bankable Feasibility Study (BFS). 1.2 Project Location and Access The Project lies in the Regency of Dairi, Province of North Sumatra. The Generation VII Dairi Contract of Work (CoW), which covers 27,420 ha was initially issued to PT Dairi Prima Mineral (Herald 80%, PT Aneka Tambang of Indonesia 20%) in 1998. The Dairi CoW is located about 120km south southwest of the provincial capital Medan and 25 km west northwest of the Regency seat of Sidikalang (see Figure 1). It is centred at about 2 0 55 N, 98 010E. The project area is accessed by bitumen highway from Medan to Sidikalang and by lower grade provincial roads to the village of Sopokomil, the remaining 3km access to the Base Camp is by foot-path. Located in the rugged Barisan Ranges, which form the backbone of Sumatra, the project area rises from a northwest sloping valley terrace level of 300-500m ASL to over 1300m ASL to the southwest. 1.3 Data Supplied ResEval was supplied with Surpac format collar surveys, down-hole surveys, assays, lithology, structure and bulk density files of the PT Dairi Prima Mineral project area. ResEval extracted the drillhole data for the Anjing Hitam deposit and carried out detailed validation of the data.

Figure1: Project location plan

2.0 GEOLOGY AND MINERALISATION

2.1 Regional Setting 1 The Dairi Project is situated within the Tapanuli Group, Lower Palaeozoic basement rocks of North Sumatra. These consist of a mixed sequence of flysch and carbonate lithologies assigned to the Carboniferous–Permian and is based on limited macro-fossil localities and may also extend into the Upper Devonian. The Tapanuli Group forms the oldest known basement sequence exposed in this region and has suffered polyphase deformation and low grade metamorphism as part of the Permo-Triassic Indosinian event. The Anjing Hitam deposit forms part of the Dairi Project and occurs as a large shale hosted massive sulphide Zn-Pb system within polyphase deformed rocks of Late Carboniferous or Early Permian age. This stratabound massive sulphide mineralisation has been interpreted as predating deformation, but may postdate sedimentation and early diagenesis. The majority of the mineralisation drilled to date occurs within a suitable host lithology cut by early NW and ENE trending structures, within a fault-bounded sub-basin on a platform margin. 2.2 Project Geology, Structure and Mineralisation

The project area is centred on the Sopokomil Dome, an antiformal structure which exposes black shale and carbonate units underlying a calciturbidite sequence of the late Palaeozoic Tapanuli Group. The Tapanuli Group in the Sopokomil Dome area has been subdivided into informal local stratigraphic units by PT Dairi Prima Mineral as shown in Table 2. The rocks have suffered polyphase deformation, including two major phases of fabric forming penetrative deformation, D1 and D2 with D3 and D4 producing more open folding, bedding slip and brittle faulting. However, due to the lateral variations and facies changes within lithostratigraphical units and the lack of well defined marker horizons it is difficult to decipher the detailed effects of the D1 – D4 deformation phases on the Anjing Hitam resource. In effect, the Main Mineralised Horizon (MMH) unit is often the most consistent and laterally continuous stratigraphic unit. The limited deformation within the thick MMH largely reflects the fact that most of the strain has been taken up by the carbonaceous shale host rocks, especially the hangingwall “pinstripe shales”. Mineralisation within the MMH is characteristically fine grained, massive and banded with compositional bands which are brassy (pyrite dominant) or bronzy (sphalerite dominant). Where the MMH becomes thinner at the margins and in the minor mineralisation in the hangingwall, structural complexity is more common with

1 After Reynolds (2004)

zones of bifurcation occurring on the western and northern margins of the deposit. Two faults were modelled within the deposit; the Jaluk Fault and the South Fault. The Jaluk Fault (Figures 2 and 3) is a significant north-south striking normal fault zone which dips steeply to the east. It offsets the MMH by approximately 15-20m vertically and has been intersected downhole in SOP144D. The South Fault is located around 9500N and strikes at approximately 260°, dipping vertically. This fault has not been intersected in any drilling and has been inferred to explain the offset of the MMH.

Group Unit Sub-Unit Description

Dagang Unit

Dolomitic shales, argillaceous dolomitic siltstones and sandstones.

Upper Julu

Laminated dolomitic carbonaceous shales, dominated by the “pinstripe shales” Sulphide bands may occur.

Julu Unit

Middle Julu

Carbonaceous siltstones, shales and coarser wacke beds. Thinly banded siliceous siltstones and black shales with abundant pyrite which occur within the main sulphide horizons and may also occur below the main sulphide horizon. Strongly deformed shale units.

Tapanuli Group

Lower Julu

Dolomitic carbonaceous shale, with poorly defined banding, gradational with overlying unit. Characterised by well developed pyrite–dolomite segregation veining and “spotting”.

Jehe Unit

Massive thick-bedded pale to dark grey dolostones with brecciation and veining. Bedding generally obscure. Carbonate and quartz veining occurs throughout the unit +/- sulphides.

Sopokomil

Unit

May be part of the Jehe Unit, possibly reflecting facies variation.

Bongkaras

Unit

Defined on the basis of massive dolostones beneath mapped Sopokomil Unit, limited to the south central part of the Dome. In outcrop it is deeply weathered and hosts secondary Zn + Pb.

Table 2: Local stratigraphy at Anjing Hitam

3.0 EXPLORATION HISTORY

3.1 Discovery Exploration work was carried out by PT Aneka Tambang in the early 1990s which located lead-zinc mineralisation in veins and anomalous stream sediments containing very high values. Follow up work by Herald in 1997 located bedded massive sulphides within the basement stratigraphy and the stratabound nature of the deposit was recognised and drilled in 1998.

Figure 2: Anjing Hitam drill cross section 9800N

Resource drilling at Anjing Hitam up to July 2004 has been carried out exclusively by diamond drilling totalling 24,189.72m in 103 holes (Table 3 and Figure 3). The focus of the BFS has been on the most coherent and drilled out prospect called the Anjing Hitam Deposit. Other prospects in the vicinity include the Basecamp and Lae Jehe (Figure 1) were estimated in 2003 and classified as Inferred Mineral Resources. These deposits will require further drilling prior to carrying out mining studies.

Figure 3: Drill hole locations

Table 3: Drilling summary at Anjing Hitam by year

*Note: Includes BFS drilling which started in October 2003

4.0 DATA COLLECTION AND PROCEDURES

4.1 Introduction A review of drilling, logging and surveying procedures on site at Anjing Hitam and an inspection of the Pt Intertek Utama Services (ITS) sample preparation facilities at Medan in Sumatra and the geochemical analysis procedures at the ITS laboratory in Jakarta was carried out. The site visit investigation criteria were as follows: • Checking drilling practice: core removal, orientation marks, core loss

recording, core competency, depth markers, downhole deviation measurement methodology.

• Check core storage, core orientation, core cutting, sampling procedures

and historical inspections of core to hard copy assay and geology plots on randomly selected holes.

• Check the methodology of specific gravity determination and the formulae

employed. • Check outcrops and mapping to confirm geological understanding. • Check collar positions, grid transformations and general site layout

against plans.

4.2 Diamond Drilling Diamond drilling was carried out initially by a local contractor using a light man portable rig and then by Pt Boart Longyear of Jakarta (Boart) using experienced Indonesian drillers. Boart was contracted in 1998 and used an Edson 431 and later a second larger rig (LF70) for the deeper drill holes. Both rigs are used on site and are moved from site to site by self winching along jungle tracks and by helicopter when necessary (Eupene, 2001). Drilling is carried out on 2 shifts (7am – 5pm – 3am). All drilling has been diamond cored using wireline triple tube HQ or NQ core sizes. The core is oriented where possible using orientation spear points.

Year No of holes Hole ID range Metres drilled 1998 3 SOP 1D - 3D 351.0 1999 2 SOP18D , SOP21D 459.7 2000 19 SOP22D - 36D, 38D, 41D - 43D 5,034.7 2001 3 SOP46D - 48D 1,283.4 2002 23 SOP65D - 87D 5,520.7

2004* 53 SOP88D - 110D, 120D - 130D, 138D - 156D 11,540.2 TOTAL 103 24,189.7

During the site visit the methods observed from the drilling practice were satisfactory and there were no fundamental flaws or problems observed from this methodology. Core recovery was generally good (95% - 100%), apart from within the fault zones and in some of the more deformed shale horizons. Diamond drilling for the BFS was carried out to: • Increase the confidence in the geological and resource model. • Define the mineralisation at Anjing Hitam to an appropriate level of

accuracy in order to develop an Ore Reserve. • Gain an understanding of the structural framework of the orebody and

gather geotechnical information for use in the underground mine design. • Provide additional sulphide material for metallurgical testwork.

Figure 4: Diamond Drilling

4.3 Surveying

4.3.1 Grid Control

Surveying at PT Dairi has been completed using licensed surveyors PT Surtech Utama Indonesia (Surtech). Surveying is carried out on the UTM grid. The adopted datum (horizontal and vertical) for the project area is the current Indonesian National Datum “DGN-95” and for all intents and purposes is identical to the GPS datum – “WGS84” and the spheroid is defined as follows: Semi Major Axis 6378137m Flattening 298.25722

Prior to the formal surveying a local ground grid was installed using tape and compass – this ground grid is neither rectilinear nor orthogonal. The local grid used in the generation of local grid plans and cross sections (Table 4) is based on the following transformation of two widely spaced “ground grid” points which yielded the best fit of the ground grid to an idealised version of the local grid:

Table 4: Local Grid and UTM Grid

The angular rotation between the UTM grid and the idealised local grid is 19.05o anticlockwise whilst the ground grid has a nominal rotation of 20o. During 2004, tests were conducted on the difference between UTM north and magnetic north. A total station instrument was used to determine the UTM bearings whilst a reflex instrument was used for the magnetic bearings. Eight separate readings were recorded with an average difference of + 0o 17’ 11” or + 0.286o for magnetic north over UTM north, i.e. magnetic north is UTM north + 0.286o. No corrections to the UTM north bearings in the drilling database were made as a result of this very small difference.

4.3.2 Collar Surveys

All the drillhole collars have been surveyed by Surtech to total station electronic distance EDM accuracy in UTM co-ordinates. A separate survey of topography was carried out in 2000 using GPS survey control on the Indonesian National Datum (DGN 95). This included the surveying of drillhole collars (as checks) and topographic surveys (2m contour plan). In conclusion, the surveying of drillhole positions matches the regional setting and has been partly validated by cross over surveys.

4.3.3 Downhole Surveying Downhole Eastman (Figure 5) single-shot surveys were taken nominally every 30m through the drill bit and at the end of holes. Drillhole deviations were generally less than 100 in both dip and azimuth.

Local Idealised Grid UTM Grid (Zone 47N) N E N E

10000 5000 307318.973 404299.879 12850 4000 309715.468 402398.480

Figure 5: Eastman digital down-hole camera

An orientation spear is run nominally every 10m and after each run in the Julu Unit and in mineralisation. Whole diamond drill core is orientated using the orientation spear points. Metre intervals are marked and recoveries are measured. Orientation marks are generally adequate to allow orientation of the core and subsequently measure the attitudes of the geological features. Problems have occurred obtaining favourable orientation marks in the more broken shale horizons in the Julu Unit and within fault zones.

The combined collar and downhole survey data indicate that the locations of the core samples are defined to sufficient accuracy to be used in a mineral resource estimate.

4.4 Core Handling, Photography and Storage Block markers for depth were routinely added and the core is stored in 1m long timber core trays and carried down to the core shed by teams of handlers. Core recovery is generally good except in fault structures. Core photography is carried out using a Nikon SQ megapixel digital camera for drilling prior to sampling and logging. The use of core trays with depth blocks, orientation marks for core orientation, tray identification and documentation were satisfactory and comply with industry standards. Core was laid out in an orientation cradle, reassembled and marked by pen for the cutting line (Figure 6).

4.5 Logging

Whole diamond drill core is logged in detail by site geologists using an evolved company standardised log form. Lithology, mineralisation, structure (Figure 7) and RQD is recorded for every metre. One criticism about this logging is that some data gathered may not be utilised and that there also there is very little room for any graphic logging on the proforma log sheet.

Figure 6: Marking core cutting line.

Figure 7: Taking structural measurements.

A summary log is created for each drillhole by the Senior Geology Manager Ian Bruce, which contains survey data, lithostratigraphy summary and descriptions of the mineralised units. Coupled with this, a drill hole cover sheet is written up containing details of the downhole surveys and contains a written section for objectives/results/comments. ResEval’s review of the drillhole logging data indicates that the standard of geological, structural and geotechnical logging is high and suitable for the development of resource models. The Julu/Jehe contact is relatively consistent and can be modelled as a 3-D surface, while the Julu/Dagang contact is more irregular and difficult to define. The Jaluk Fault and the Southern Fault have been modelled as 3-D surfaces based on the cross sectional interpretations.

4.6 Core Sampling Due to the visible nature of the metal sulphide mineralisation, assay sampling can be restricted to the mineralised intercepts. Generally the geologists sample 1m of the waste core both footwall and hangingwall to the mineralisation and sample the mineralised zones in 1m intervals. The core is marked out with a cutting line by the geologists and core sampling is carried out by an experienced sampling geotechnician using an industry standard diamond saw. After the core has been logged in detail, sawn half core samples are bagged on site in calico bags. One piece of core approximately 15cm long is placed in a plastic sample bag inside the calico bag for SG determination by water displacement methods at the ITS prep laboratory at Medan. Sample numbers are written on the bags and on tags placed inside the bags and the samples are then sealed and boxed for carrying to the Sopokomil village where they are transported by a vehicle to Medan by a senior company employee. 4.7 Mapping

Outcrop mapping has been carried out throughout the Sopokomil Dome area by Herald exploration geologists and by Neal Reynolds, mainly along stream sections and access tracks. The mapped surface outcrops were used as much as possible when developing the 3-D geological and resource model. 4.8 Sample Preparation Core samples are sent to the ITS sample preparation facility in Medan and checked against the submission sheets. The total sample submitted is dried for approximately 10 hrs, to a core temperature of 1100C. The samples are then crushed using a Jaques 8“ by 4“ laboratory jaw crusher. The material is milled in a LM5 mill to a nominal 90% passing 75 microns. All crushing material goes directly to pulverizing. An analytical pulp of approximately 200–250g is subsampled from the bulk and the milled

residue is retained for future reference. The sample preparation procedure is illustrated in Figure 8. All preparation equipment is cleaned with barren quartz prior to the commencement of the job. High pressure air is applied to clean the working jaw crusher and dust extraction was also used to minimise contamination. The pulp is stored in the paper bags of 200–250g each.

Figure 8: Sample preparation procedure

4.9 Geochemical Analysis Following preparation, pulp samples are sent to the ITS laboratory in Jakarta where the samples (apart from those designated as “ore grade” by site) are subjected to a screening analysis for Ag, Cu, Pb and Zn by AAS geochemical analysis using a perchloric/hydrochloric acid digest as follows: Stage 1: All samples are initially analysed as a first pass screening process for Ag, Cu, Pb and Zn by geochemical analysis using a perchloric/hydrochloric acid digest (HCl / HClO4) with an AAS finish. Stage 2: Samples designated as “ore grade” and those exceeding upper limits for the previous digest are re-digested for a “total digest” using a triple acid digestion of perchloric/nitric and hydrochloric acid (HCl/HNO3/HClO4) followed by an accurate volumetric finish in order to allow high concentrations of the elements to be analysed. 4.10 Bulk Density Data Specific gravity (SG) measurements were obtained from full core samples using a cradle to weigh the dry weight and then the wet weight after being submerged in a bucket of water. The cradle weight was then subtracted from each measurement. The core was not waxed, however the core was competent and there were no minor voids and in most cases no fracture zones within the core that would bias the determination. SG and bulk density testing was carried out on the majority of samples sent for analysis to the ITS prep laboratory at Medan used the following procedures:

1. Approximately 15cm of drill core was used per each 1m sample of mineralisation.

2. The sample is first weighed as wet weight (W1) 3. It is then dried at 105°C for 12 hours and weighed in air (W2) 4. The sample is weighed in water (W3)

SG is calculated according to the following formula:

SG = weight in air / (weight in air – weight in water)

SG = (W2) / (W2) – (W3)

4.11 Quality Control PT Dairi Prima Mineral used the following quality control practices during their drilling programme at Anjing Hitam: • Insertion of a standard every 20 m with the core samples (Figure 9). • External check analyses were performed by Cominco on 12 mineralised

half core samples crushed to -2mm, when they entered the project (Figure 10).

• In 2000, 42 coarse crushed residues analysed by Amdel laboratory in Perth resulted in good correlation with the ITS laboratory.

• In 2004, 134 coarse crushed residues were analysed by Amdel laboratory in Perth which resulted in good correlation (Figures 11-13).

ResEval considers the quality control procedures used by PT Dairi Prima Mineral to be appropriate. Internal procedures for monitoring quality control are routinely carried out by ITS. These include the use of external standards and blanks supplied by Canmet and Gannet. Reports on internal standard monitoring are provided to the client. A sample tracking system known as the Laboratory Information Management System (LIMS) for sample tracking, quality control and reporting using bar coding is employed by ITS. ITS is ISO 17025 accredited and involved in an international (Geostats) round robin laboratory checking system.

Standard Sample GBM 995-8

0123456789

101112131415

C0577

C0581

C0667

C0807

C0808

C0858

C0960

C0961

B1071

B1202

B1203

B1314

B1315

B1350

% Z

n &

Pb

40

42

44

46

48

50

52

54

56

58

60

62

64

66

68

70

ppm

Ag

Zn

Pb

Ag

Figure 9: Example showing Standards Results

Figure 10: Herald/Cominco Pb check analyses

Zinc Assays Correlation

Amdel vs ITS

0.00

10.00

20.00

30.00

40.00

50.00

0.00 10.00 20.00 30.00 40.00 50.00

Zn % Amdel

Zn %

ITS

Figure 11: Amdel vs ITS check assays – zinc

Lead Assays Correlation

Amdel vs ITS

0.00

10.00

20.00

30.00

40.00

50.00

60.00

0.00 10.00 20.00 30.00 40.00 50.00 60.00

Pb % Amdel

Pb %

ITS

Figure 12: Amdel vs ITS check assays – lead

Silver Assays Correlation

Amdel vs ITS

0

50

100

150

200

0 50 100 150 200

Ag ppm Amdel

Ag

ppm

ITS

Figure 13: Amdel vs ITS check assays – silver

Examination of the sample preparation and the assay laboratory indicated a high standard of operation. The testing procedures were of high quality, and the management well directed.

5.0 DATABASE DEVELOPMENT AND VALIDATION

5.1 Introduction Data used for the resource estimate was provided to ResEval by Herald and included an Access database of exploration drillholes and Surpac data files with up-to-date drilling information. These included collar surveys, down-hole surveys, assays, lithology, structure and bulk density files for the PT Dairi Prima Mineral project area. ResEval extracted the drillhole data for the Anjing Hitam deposit and carried out detailed validation of the data. 5.2 Collar and Downhole Survey Data Database verification was carried out by ResEval on a selected number of holes for collar location, survey information and assays. The review was carried out in the Herald Perth Office. A total of 30 holes were checked against original collar surveys, 17 holes for downhole surveys and 13 holes for assays against original laboratory reports. Table 5 below lists drillholes checked. All collar and assay data was found to be correct when compared with the original data, however, a few discrepancies were found (albeit minor in all cases) in the downhole survey data. The discrepancies appeared to be a result of transcription or data entry error given that data was taken from the single-shot camera and manually written on drillhole logs, whilst also being manually entered into the database.

Holes checked for downhole surveys Holes checked for assays SOP3D SOP76D SOP1D SOP121D SOP23D SOP80D SOP22D SOP123D SOP30D SOP95D SOP32D SOP127D SOP33D SOP99D SOP41D SOP130D SOP34D SOP102D SOP67D SOP43D SOP120D SOP77D SOP46D SOP123D SOP85D SOP47D SOP139D SOP90D SOP74D SOP98D

Table 5: Database Verification.

Following this check, a full database review for downhole surveys was undertaken by B. Kirkpatrick of Herald in consultation with the Sopokomil site office. A corrected database was subsequently provided to ResEval.

5.3 Assay Data Checks were carried out on total hole depth, final sample depth, overlapping and missing samples and also detection limits and zinc equivalent formulas were checked.

6.0 GEOLOGICAL MODELLING

6.1 Introduction East-west drill hole resource cross-sections were extracted at 50m intervals using the local grid. For all cross sections, the assay fields Zn, Pb and Ag were plotted with the geology field called lithology. Mineralisation at Anjing Hitam occurs as massive sulphides within the Julu Carbonaceous Shale. The MMH occurs as a discrete sulphide lens up to 25 thick (averaging ~12m) which strikes approximately NW-SE, dipping at about 400 to the east. Several other mineralised lenses occur throughout the shale unit although they are generally less than 5m thick and of lower tenor than the MMH. Sectional interpretations by N. Reynolds were used as a guide for the ResEval interpretations. Units were then digitised and reviewed with him on screen to validate the interpretations three-dimensionally. No minimum downhole length was used as the interpretation included massive sulphide zones down to 20cm wide with no edge dilution. Minor intervals of internal dilution were included, particularly in the peripheral zones of the deposit where the mineralisation became more disseminated, to maintain consistency of the geological model. Two faults were modelled within the deposit: the Jaluk Fault and the South Fault. The Jaluk Fault is a significant north-south striking normal fault zone which dips steeply to the east. It offsets the MMH by approximately 15-20m vertically and has been intersected downhole in SOP144D. The South Fault is located around 9500N and strikes at approximately 260°, dipping vertically. This fault has not been intersected in any drilling and has been inferred to explain the offset of the MMH. Weathering profiles were provided to ResEval in hard copy cross sections and based on the information in the drillhole database all material was considered to be fresh rock for the estimation. 6.2 Preparation of Wireframes The interpreted sectional outlines were manually triangulated to form three-dimensional models (wireframes) as shown in Figures 14 and 15. The MMH is made up of objects 1-3, whilst peripheral zones consist of objects 10-21. In order to form ends to the wireframes, the end section strings were copied to a position midway to the next section and adjusted to match the dip, strike

and plunge of the zone. The wireframed objects were validated using Surpac software and set as solids. A wireframe was also constructed for the Julu Footwall (footwall1.dtm) based on interpretations provided by N. Reynolds.

Figure 14: Cross section view of Anjing Hitam resource wireframes

Figure 15: Long section view of Anjing Hitam resource wireframes (looking west). The pink, yellow and southern green bodies are Objects 1, 2 and 3 respectively of the MMH, whilst the other bodies are all part of the UMH.

7.0 STATISTICAL ANALYSIS

7.1 Introduction

An Access database containing all drill holes in the Anjing Hitam sector was provided to ResEval by Herald. Surpac string and data files for the previous (Kirkpatrick, 2003) estimate were also provided by Herald. A summary of the drilling data within the project area is shown in Table 6.

Sample Type In Sopokomil Area Used in Anjing Hitam Estimate

No. Metres No. Metres Core Holes 140 32,492.7 103 24,189.7

Table 6: Summary of Anjing Hitam drilling

7.2 Sample Length Analysis

The 3DMs of the mineralised zones were used to code the database to allow identification of the resource intersections. Separate intersection files were generated for each object. The samples inside the resource wireframes were then extracted to allow analysis of the various sample lengths. The majority of samples were clearly shown to be 1m in length as shown in Figure 16 below.

Distribution of Sample Intervals in Anjing Hitam Resource

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Figure 16: Distribution of raw sample lengths in Anjing Hitam resource

Surpac software was used to extract 1.0m downhole composites within the intervals coded as resource intersections. The composites were checked for spatial correlation with the objects, the location of the rejected composites, and zero composite values. Individual composite files were created for each object in the wireframe models.

7.3 Compositing and Data Coding The composite sample data and the original sample data for the resource zone were imported into GeoAccess software for analysis. The data was separated into the MMH and other peripheral mineralisation. Summary statistics for the MMH are shown in Table 7.

Parameter AG PB ZNNumber 976 976 976Minimum 0.05 0.00 0.00Maximum 164.00 52.10 39.40 Mean 12.90 9.71 15.32Median 9.50 8.60 15.90Std Dev 13.44 6.18 6.65Variance 180.52 38.23 44.18Std Error 0.01 0.01 0.01Coeff Var 1.04 0.64 0.43 Sichel Stats Mean 12.83 10.20 17.36V 0.59 0.51 0.60Gamma 1.35 1.28 1.35 Percentiles 10 4.00 3.36 4.9620 5.00 5.52 10.7030 6.98 6.75 13.6040 8.00 7.80 14.8450 9.50 8.60 15.9060 11.00 9.40 16.7070 14.00 10.70 17.7080 17.60 12.70 19.4090 24.00 17.48 23.7495 32.00 20.90 26.9297.5 41.68 24.46 28.7099 58.49 30.15 31.35

Table 7: Summary statistics of Anjing Hitam 1m resource composites – MMH

7.4 Descriptive Statistics and Application of Cut-off Grades To assist in the selection of appropriate high grade cuts, the composite data for the main zone was imported into GeoAccess software and a log-probability plot was generated (Figure 17). It was decided that no high grade cut would be used due to the absence of erratic high grade outliers in the sample populations for each element.

Figure 17: Probability plot Anjing Hitam 1m composite data – MMH (brown = Zn, blue = Pb, green = Ag)

8.0 VARIOGRAPHY STUDY

8.1 Methodology

The 1m assay composites from only the MMH mineralisation were reviewed. It was considered that due to the relatively small number of samples in most of the minor zones, variographic analysis was not warranted. Therefore ID2 interpolation was to be used in the minor zones.

8.2 Model Variography

Variography of the main zone was carried out using GeoAccess software. To determine the nugget, an omnidirectional variogram with a 1m lag was used, reflecting the down-hole composite interval. This resulted in a well structured variogram for Zn, Pb and Ag. The Zn variogram is shown in Figure 18. It was fitted to a nested two structure spherical model.

Figure 18: Omnidirectional variogram for Zn main zone

Horizontal directional variograms were then derived using 25m lags reflecting the average drill hole spacing in the better-drilled area. The direction of greatest continuity was found to be 010o as shown in Figure 19 and was modelled using the nugget derived from the omni-directional variogram.

Figure 19: 010o horizontal variogram for Zn main zone

Down dip variograms were then derived in a plan perpendicular to that direction. The down dip variograms were generally poor. The greatest continuity was found to be in a dip direction of 30o to the east. The down dip variogram was fitted using the nugget, C1 and C2 values determined from the horizontal model.

Figure 20: Down dip variogram at -30o to 100o for Zn main zone

Comprehensive plots of the variograms are included in Appendix 3. A summary of the fitted variogram models is shown in Table 8. The results of the variography generally matched the interpreted geology and geometry of the main Primary Zone with an overall approximately northerly strike and moderate easterly dip to the mineralisation. The low nugget and long ranges evident in the variograms confirm the excellent continuity of grade which was observed in the drilling data. The short range structures in the main axis for Zn and Pb were both 75m, which is greater than the typical drill hole spacing and suggests that the

drilling should have defined the grade of the deposit with a high degree of confidence.

Nugget C1 A1 C2 A2

Variable: Zn Relative Variance Omnidirectional 1m Lag 8% 24% 3.5 68% 23 Horizontal 010o 25m Lag 39% 75 53% 175 Down Dip -30o/100o 25m Lag 39% 60 53% 90

Nugget C1 A1 C2 A2 Variable: Pb Relative Variance Omnidirectional 1m Lag 16% 27% 3 57% 9 Horizontal 010o 25m Lag 64% 75 20% 120 Down Dip -30o/100o 25m Lag 64% 75 20% 90

Nugget C1 A1 C2 A2 Variable: Ag Relative Variance Omnidirectional 1m Lag 12% 25% 3 63% 13 Horizontal 010o 25m Lag 45% 50 42% 175 Down Dip -30o/100o 25m Lag 45% 50 42% 90

Table 8: Variogram parameters for Dairi Main Zone

9.0 BLOCK MODEL DEVELOPMENT

9.1 Introduction The current estimate was carried out in the ResEval Perth office during August 2004. Resource outlines were prepared at a 5% zinc equivalent cut-off grade and used to create wireframes within which resource estimation was carried out. Surpac Mining software and Datamine software were used for all modelling and estimation procedures.

9.2 Block Model Extents and Block Size A block model was created to encompass the full extent of the deposit. Block model parameters are listed in Table 9. The block model used a primary block size of 10m EW by 20m NS by 2m vertical with sub-blocking to 2.5m by 5m by 0.5m. The parent block size was selected on the basis of 50% of the average drill hole spacing. The small sub-block size was necessary to provide sufficient resolution to the block model within narrow parts of the wireframe.

Table 9: Anjing Hitam deposit block model parameters

9.3 Density Assignments

The database provided by Herald included fields for laboratory derived densities (‘sg_lab’) and resource densities (‘sg_res’). The ‘sg_res’ field included all the ‘sg_lab’ data, plus estimates of the density for other zones within the wireframes not measured by the laboratory. The ‘sg_lab’ data includes the results from laboratory density determinations using the ‘Immersion’ method. A total of 719 measurements were available. For the ‘sg_res’ field, estimates were provided by B. Kirkpatrick of Herald and took into account the rock type, sulphide composition and grade. Approximately 30% of the values in the ‘sg_res’ were estimates. The ‘sg_res’ field was then interpolated within the ID2 estimate, using the same parameters as for the Zn, Pb and Ag fields. The average density for the deposit was estimated to be 4.23t/m3. Figure 21 shows the interpolated densities for the MMH.

Block Model Parameters Y X Z Origin (minimum y,x,z) 9,300 4,700 450 Extent 1000 800 500 Block Size (Sub-blocks) 20m (5) 10m (2.5) 2m (0.5) Rotation None Attributes:

kvar_zn_ok Kriging variance for zinc kvar_pb_ok Kriging variance for lead kvar_ag_ok Kriging variance for silver

kvar Kriging variance min_dis_ok Distance to nearest sample – OK model av_dis_ok Average distance to samples – OK model

num_sam_ok Number of samples used for block grade interpolation – OK model Zn_ok Block zinc grade – OK model Pb_ok Block lead grade – OK model Ag_ok Block silver grade – OK model

min_dis Distance to nearest sample – ID model av_dis Average distance to samples – ID model

num_sam Number of samples used for block grade interpolation – ID model Zn_pct Block zinc grade – ID model Pb_pct Block lead grade – ID model Ag_pct Block silver grade – ID model

pass 1= interpolated in first pass, 2= interpolated in second pass, 3=interpolated in third pass

min_dis_sg Distance to nearest sample – sg av_dis_sg Average distance to samples – sg

num_sam_sg Number of samples used for block grade interpolation – sg sg Bulk Density

mined Y,N pod Object number

Class Mes, Ind, Inf Class_code Mes=1, Ind=2, Inf=3

Figure 21: SG interpolation for the Anjing Hitam MMH

9.4 Block Model Validation

In order to check that the interpolation of the block model correctly honoured the drilling data, validation was carried out by comparing the interpolated blocks to the sample composite data for both the MMH (objects 1-3) and the whole deposit (objects 1-3,10-21). Validation results for the MMH are summarised in Figures 22 and 23 and Table 10. Full details of the validation are included in Appendix 2 of this report.

Figure 22: Anjing Hitam Main Zone validation plot by Northing

Anjing Hitam Comparison of Model and Composites by Northing - MMH

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Figure 23: Anjing Hitam Main Zone validation plot by RL

Table10: Anjing Hitam deposit block model validation by pod

The validation plots show a reasonable correlation between the composite grades and the block model grades for both the comparison by elevation and by northing. In general, the trends shown by the raw data are honoured by the block model.

W ireframe ResourceW ireframe Volume Volume Zn% Pb% Number Zn% Pb%1 (MMH) 1,081,853 1,081,344 16.06 9.94 614 15.17 9.852 (MMH) 629,499 629,375 15.74 9.53 320 15.29 9.193 (MMH) 63,745 63,775 16.95 9.87 39 15.62 8.4910 3,949 3,988 8.34 4.19 3 8.44 4.411 2,289 2,288 11.09 6.16 6 12.30 7.24212 19,113 19,125 17.15 9.26 8 16.23 8.84413 18,226 18,163 7.83 4.71 24 8.21 4.7715 2,877 2,900 9.41 5.2 6 8.20 4.82116 6,011 6,013 10.35 4.35 11 9.51 4.02617 22,720 22,919 15.53 9.56 23 15.35 9.21918 10,163 10,194 10.2 5.56 12 9.37 5.17319 2,313 2,381 9.78 7.57 5 11.83 7.90920 7,517 7,513 12.86 4.34 11 12.91 3.28721 15,394 15,500 11.48 6.27 23 11.25 6.109Total 1,885,669 1,885,475 15.77 9.62 1,105 14.77 9.17

Block ModelSamples

Anjing Hitam Comparison of Model and Composites by 20m Bench - MMH

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10.0 GRADE ESTIMATION

10.1 Introduction

The last published Mineral Resource estimate was completed by Herald in March 2003 for PT Dairi Prima Mineral (Kirkpatrick, 2003). The method used was ID3 and reported using a lower cut-off value of 5% zinc equivalent (where 1% Pb was equivalent to 0.55% Zn and 1g/t Ag is equivalent to 0.005% Zn). An estimate using similar parameters was also completed by Eupene in 2001. A summary of the results and a comparison with the ResEval estimate is shown in Table 11.

M Tonnes Zn Pb Ag Zn_Eq Estimate % % g/t %

Eupene 2001 ID3 5% COG 7.5 16.7 10.3 14 27.0 Kirkpatrick 2003 ID3 5% COG 8.0 15.8 9.7 12 21.3

ResEval 2004 OK 5% COG 8.0 15.8 9.6 12 23.5* * Zinc equivalent for the ResEval 2004 estimate used the formula: Zn% + 0.8*Pb%

Table 11: Previous mineral resource estimates The similarity of the resource estimates demonstrates the robustness of the deposit in both tonnes and grade. The difference between the zinc equivalent values is a function of the changing zinc and lead prices. 10.2 Ordinary Kriging Ordinary kriging (OK) was initially selected for grade interpolation to incorporate deposit variography into the model. Kriging was only attempted on the MMH due to the small number of samples in most other zones, hence restricting variography for these zones. OK parameters used in the OK estimate are shown in Table 12.

Parameter Zn Pb AgBearing 10o 10o 10o

Dip -30o -30o -30o

Plunge 0o 0o 0o

Major-Semi Major Ratio 1.9 1.3 1.9Major-Minor Ratio 7.6 13.3 13.5

Search Radius 210m 144m 210m

Max Vertical Search 999 999 999

Minimum Samples 4 4 4Maximum Samples 40 40 40

Table 12: OK interpolation parameters for MMH

For the peripheral zones of the deposit (other than the MMH), the ID2 algorithm was used for grade interpolation. An ID2 check estimate was also performed on the MMH. All objects used an oriented ellipsoid search for the interpolation. For the MMH (objects 1 & 2), a search radius of 60m was used along strike by 30m down dip by 10m across strike. This was based on lode geometry and drill hole spacing. The remaining objects used an isotropic search. Almost all blocks were estimated in the first pass (97.8%). Those remaining unestimated after the first pass were then interpolated by doubling the search distance to 120m (2.1%). A third pass run with the search distance increased to 300m filled all blocks in the model. Parameters used in the estimate are listed in Table 13.

Parameter MMH – Object 1 MMH – Object 2 Others Bearing 335o 335o 0o

Dip -35o -30o 0o Plunge 20o 15o 0o

Major-Semi Major Ratio 2 2 1 Major-Minor Ratio 6 6 1

Search Radius 1=60m, 2=120m, 3=300m

1=60m, 2=120m, 3=300m

1=60m, 2=120m, 3=300m

Max Vertical Search 999 999 999

Minimum Samples 2 2 2 Maximum Samples 32 32 32

Table 13: ID2 interpolation parameters

The results of the Mineral Resource estimate for the Anjing Hitam deposit are tabulated in detail in Appendix 1 of this report. A summary of the estimate is shown in Table 14.

Category Zone M Tonnes Zn % Pb % Ag g/t Zn_Eq % Measured MMH 5.4 16.5 10.2 13 24.7 Indicated MMH 1.8 14.3 8.5 11 21.1 Indicated Minor 0.5 16.3 9.5 13 23.8

Total Measured + Indicated 7.7 16.0 9.8 12 23.8 Inferred Minor 0.3 10.3 5.4 11 14.6

Total Inferred 0.3 10.3 5.4 11 14.6 TOTAL 8.0 15.8 9.6 12 23.5

* Zinc equivalent calculated using the formula: Zn% + 0.8*Pb% Table 14: Anjing Hitam Deposit August 2004 undiluted mineral resource estimate

To show the spatial distribution of grade through the Anjing Hitam MMH, a plan projection of the resource blocks has been prepared and is shown in Figure 24. The figure shows a core of high grade mineralisation (>30% Zn_Equivalent) around the Jaluk Fault (and possibly displaced dextrally).

10.3 Validation of Estimates

Figure24: Zinc equivalent grade distribution in plan – MMH

To quantify the tonnage and grade distribution throughout the deposit, a bench breakdown has been prepared and is shown graphically in Figure 25.

Figure 25: Anjing Hitam deposit mineral resource –20m bench breakdown

Anjing Hitam Deposit Tonnes and Grade per 20m Bench

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The grade-tonnage curve for the resource is shown in Figure 26 and is detailed in Appendix 1.

Anjing Hitam Deposit Grade Tonnage Curve

01,000,0002,000,0003,000,0004,000,0005,000,0006,000,0007,000,0008,000,0009,000,000

0 5

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Figure 26: Anjing Hitam grade-tonnage curve The uniformly high grade nature of the deposit is demonstrated by the grade-tonnage curve. The majority of the resource has a grade greater than 20% zinc equivalent.

An Inverse Distance squared (ID2) check model was completed for the Anjing Hitam deposit to compare to the Ordinary Kriging estimate. The results were almost identical, with the Kriging model producing slightly higher grades for both zinc and lead. The results are shown in Table 15 below.

Tonnes Zn Pb Ag Zn_Eq Estimate mT % % g/t % ResEval 2004 OK 5% COG 8.0 15.8 9.6 12 23.5 ResEval 2004 ID2 5% COG 8.0 15.7 9.6 12 23.4

Table 15: Comparison of OK v ID2 Estimates

11.0 RESOURCE REPORTING

11.1 Resource Classification The Anjing Hitam deposit shows strong continuity of the MMH allowing the drillhole intersections to be modelled into a coherent, geologically robust wireframe. Good consistency is evident in the thickness of the structure and the grade distribution appears regular.

The average drillhole cross section spacing for this style of deposit is considered adequate to define the resource zones in thickness, lateral extent and attitude with a reasonable degree of confidence. This is supported by the average hole spacing (50m) being less than the range of continuity measured by the variography (75m for Zn and Pb). ResEval considers that the confidence level is sufficient to categorise the majority of the mineralisation as a Measured and Indicated Mineral Resource. The central portion of the MMH was classed as Measured. The Indicated portion of the resource included: • the western side of the MMH where the zone bifurcates; • the north-eastern end of the MMH (object 2) where the mineralisation

becomes more stockwork rather than massive sulphide; • the MMH north of 9990N; • the south-east corner of the MMH (object 2) where the orientation and dip

of the mineralisation changes; • the MMH immediately south of the South Fault; and • some peripheral zones which displayed good continuity.

The resource block model has an attribute “class” for all blocks within the resource wireframes coded as either “mes” for Measured, “ind” for Indicated or “inf” for Inferred. The Measured Indicated and Inferred portions of the deposit are shown in Figures 27

Figure 27: Mineral resource classification in plan – all zones (red=Inferred, green=Indicated, blue=Measured)

12.0 CONCLUSIONS AND RECOMMENDATIONS The Anjing Hitam resource represents a significant zone of high grade Zn-Pb-Ag mineralisation with consistent grade distribution. The main mineralised horizon (MMH) shows excellent continuity along strike and down-dip with consistent thickness and well defined boundaries. The site visit procedures review is summarised as follows:

• Core recovery is reasonably good apart from the deformed shale horizons and within fault zones

• Recording of drill depths was correct • The current drill programme was well organised, efficiently run and all

holes reached planned targets and depths. • Downhole surveys were accurate and frequent • Core storage is adequate, the facility will need to be expanded when

underground drilling takes place • Core cutting, bagging, sampling and dispatch methods were

satisfactory • SG determination methodology was satisfactory as was the formula

applied to the weights • Sample preparation and analysis were carried out to Australian mining

industry standards • The grid transformations and the transformation of the azimuth

direction was correct • Collar elevations were not checked • The current geological understanding demonstrates good continuity

between sections for the lodes and domains • A check of the hardcopy sections and the grade database correlated

with the randomly selected drillholes inspected on site was carried out and proved to be accurate.

There appears to be little potential to expand the Anjing Hitam resource beyond its existing limits. It is possible that some of the minor hangingwall lenses, may prove to be larger than currently defined, however their potential to enhance production may be reduced by the difficult ground conditions expected in the hangingwall Julu sequence.

Further work on the deposit should include drilling of both the Jaluk and South Fault zones, however this will need to be done from underground due to the orientation of the faults and the lack of appropriate surface drill locations. The deposit appears to have excellent potential for profitable exploitation by underground mining. Appropriate dilution parameters need to be included in any mining studies on the deposit.

13.0 REFERENCES

Eupene, G.S. (2001). Initial Resource Estimation Report, Sopokomil Prospect, Dairi Project, North Sumatra, Indonesia, as at January, 2001. Report for International Annax Ventures Inc.

Reynolds, N.A., (2004). Geology of the Anjing Hitam Resource, Dairi Project

North Sumatra, Indonesia. Unpublished Report for Herald Resources Ltd.

Kirkpatrick, B.L. (2003). Mineral Resource Estimates for the Anjing Hitam – Base Camp and Lae Jehe Sectors, Sopokomil Prospect, Dairi Project, North Sumatra. PT. Dairi Prima Mineral.

14.0 APPENDICES Appendix 1: Anjing Hitam August 2004 resource tables Appendix 2: Anjing Hitam resource validation tables Appendix 3: Anjing Hitam variography Appendix 4: Anjing Hitam Surpac string file descriptions

Appendix 1

Anjing Hitam Deposit

August 2004 Resource Tables

APPENDIX 1 – AUGUST 2004 RESOURCE TABLE

MEASUREDBench

Top Tonnes Zn Pb Ag Zn_Eq Tonnes Zn Pb Ag Zn_Eq Tonnes Zn Pb Ag Zn_EqRL T % % % % T % % % % T % % % %840820800 6,311 11.89 11.92 20.25 21.43 6,311 11.89 11.92 20.25 21.43780 84,781 11.12 13.79 28.88 22.15 84,781 11.12 13.79 28.88 22.15760 123,993 11.03 13.65 29.94 21.95 123,993 11.03 13.65 29.94 21.95740 177,351 15.72 10.51 16.92 24.13 177,351 15.72 10.51 16.92 24.13720 426,417 17.58 10.78 12.58 26.21 426,417 17.58 10.78 12.58 26.21700 981,033 17.18 10.43 12.72 25.53 981,033 17.18 10.43 12.72 25.53680 992,843 17.73 10.43 13.66 26.08 992,843 17.73 10.43 13.66 26.08660 372,661 17.14 9.87 11.95 25.03 372,661 17.14 9.87 11.95 25.03640 677,031 17.62 11.51 12.35 26.83 677,031 17.62 11.51 12.35 26.83620 691,891 16.12 9.92 10.20 24.06 691,891 16.12 9.92 10.20 24.06600 513,307 14.95 8.48 9.14 21.73 513,307 14.95 8.48 9.14 21.73580 304,421 13.97 7.74 9.44 20.16 304,421 13.97 7.74 9.44 20.16560 79,921 13.31 7.00 8.85 18.92 79,921 13.31 7.00 8.85 18.92540 978 13.30 6.76 9.11 18.71 978 13.30 6.76 9.11 18.71

TOTAL 5,432,918 16.49 10.23 12.67 24.68 5,432,918 16.49 10.23 12.67 24.68

INDICATEDBench

Top Tonnes Zn Pb Ag Zn_Eq Tonnes Zn Pb Ag Zn_Eq Tonnes Zn Pb Ag Zn_EqRL T % % % % T % % % % T % % % %840 2,279 14.43 7.83 9.17 20.69 2,279 14.43 7.83 9.17 20.69820 48,529 13.85 8.41 9.47 20.58 48,529 13.85 8.41 9.47 20.58800 143,977 14.09 8.08 9.90 20.55 143,977 14.09 8.08 9.90 20.55780 335,572 13.14 7.94 10.13 19.49 335,572 13.14 7.94 10.13 19.49760 236,330 12.24 8.13 11.80 18.75 2,088 14.78 8.28 13.44 21.41 238,418 12.26 8.13 11.81 18.77740 266,947 14.74 8.65 11.58 21.66 33,379 13.62 7.52 11.32 19.64 300,325 14.62 8.52 11.55 21.44720 316,885 16.49 9.74 12.84 24.28 27,873 10.82 5.76 6.48 15.43 344,758 16.03 9.42 12.33 23.56700 124,203 16.38 9.70 12.27 24.13 74,808 16.59 8.96 10.95 23.76 199,011 16.46 9.42 11.77 23.99680 52,554 16.49 9.15 13.68 23.81 12,036 15.22 7.79 8.74 21.45 64,590 16.25 8.90 12.76 23.37660 21,828 17.50 9.92 13.32 25.43 44,749 17.05 10.67 10.17 25.59 66,576 17.20 10.42 11.20 25.54640 106,376 15.00 7.88 10.35 21.31 47,564 14.50 8.95 12.07 21.66 153,940 14.85 8.21 10.88 21.42620 269,921 15.24 8.62 11.88 22.14 453 11.53 5.86 3.24 16.22 270,374 15.23 8.62 11.87 22.13600 25,605 15.58 9.07 16.37 22.84 25,605 15.58 9.07 16.37 22.84580 82,562 15.29 9.28 10.45 22.71 82,562 15.29 9.28 10.45 22.71560 31,777 14.69 9.14 12.57 22.00 31,777 14.69 9.14 12.57 22.00540

TOTAL 2,065,364 14.68 8.68 11.51 21.62 242,950 15.10 8.64 10.46 22.02 2,308,314 14.72 8.68 11.40 21.66

INFERREDBench

Top Tonnes Zn Pb Ag Zn_Eq Tonnes Zn Pb Ag Zn_Eq Tonnes Zn Pb Ag Zn_EqRL T % % % % T % % % % T % % % %840820800 119 10.81 5.28 5.52 15.03 119 10.81 5.28 5.52 15.03780 11,232 9.68 4.92 6.86 13.61 11,232 9.68 4.92 6.86 13.61760 25,943 7.83 4.42 15.18 11.36 25,943 7.83 4.42 15.18 11.36740 35,298 7.68 4.99 18.39 11.67 35,298 7.68 4.99 18.39 11.67720 14,256 9.86 5.30 15.59 14.10 14,256 9.86 5.30 15.59 14.10700 10,507 8.72 4.47 22.82 12.29 10,507 8.72 4.47 22.82 12.29680 48 8.34 4.19 24.65 11.69 48 8.34 4.19 24.65 11.69660 17,654 9.11 5.24 6.48 13.30 17,654 9.11 5.24 6.48 13.30640 51,212 11.31 5.30 6.04 15.55 51,212 11.31 5.30 6.04 15.55620 25,322 11.25 4.61 4.62 14.94 25,322 11.25 4.61 4.62 14.94600 7,597 18.75 10.36 17.98 27.04 7,597 18.75 10.36 17.98 27.04580 18,217 12.68 6.57 9.33 17.94 18,217 12.68 6.57 9.33 17.94560 13,170 11.99 6.69 6.27 17.34 13,170 11.99 6.69 6.27 17.34540

TOTAL 38,984 13.63 7.35 9.98 19.51 191,589 9.61 4.96 11.09 13.58 230,573 10.29 5.36 10.90 14.58

Anjing Hitam DepositSeptember 2004 Resource Estimate

MMH MINOR ZONES TOTAL



TOTALBench

Top Tonnes Zn Pb Ag Zn_Eq Tonnes Zn Pb Ag Zn_Eq Tonnes Zn Pb Ag Zn_EqRL T % % % % T % % % % T % % % %840 2,279 14.43 7.83 9.17 20.69820 48,529 13.85 8.41 9.47 20.58800 150,286 13.99 8.24 10.33 20.58 119 10.81 5.28 5.52 15.03 150,405 13.99 8.24 10.33 20.58780 420,357 12.73 9.12 13.91 20.02 11,232 9.68 4.92 6.86 13.61 431,588 12.65 9.01 13.73 19.85760 360,319 11.82 10.03 18.04 19.85 28,031 8.35 4.71 15.05 12.11 388,349 11.57 9.65 17.82 19.29740 444,305 15.13 9.39 13.71 22.65 68,677 10.57 6.22 14.96 15.54 512,981 14.52 8.97 13.88 21.70720 743,292 17.12 10.34 12.69 25.39 42,129 10.50 5.60 9.56 14.98 785,421 16.76 10.09 12.52 24.83700 1,105,237 17.09 10.35 12.67 25.37 85,314 15.62 8.41 12.41 22.35 1,190,551 16.98 10.21 12.65 25.15680 1,045,404 17.67 10.37 13.66 25.97 12,083 15.19 7.78 8.80 21.41 1,057,487 17.64 10.34 13.60 25.92660 394,489 17.16 9.87 12.03 25.05 44,749 17.05 10.67 10.17 25.59 439,237 17.15 9.95 11.84 25.11640 783,405 17.27 11.01 12.08 26.08 65,219 13.04 7.95 10.56 19.40 848,624 16.94 10.77 11.96 25.57620 961,821 15.87 9.56 10.67 23.52 51,664 11.31 5.31 6.01 15.56 1,013,485 15.64 9.34 10.43 23.11600 546,516 15.03 8.54 9.60 21.86 25,322 11.25 4.61 4.62 14.94 571,838 14.86 8.37 9.38 21.55580 405,196 14.18 8.00 9.64 20.58 405,196 14.18 8.00 9.64 20.58560 124,869 13.52 7.52 9.53 19.54 124,869 13.52 7.52 9.53 19.54540 978 13.30 6.76 9.11 18.71

TOTAL 7,537,180 15.98 9.79 12.34 23.81 434,536 12.68 7.02 10.74 18.30 7,971,716 15.80 9.64 12.25 23.51


Anjing Hitam Deposit Tonnes and Grade per 20m Bench

0

200,000

400,000

600,000

800,000

1,000,000

1,200,000

1,400,000

840

820

800

780

760

740

720

700

680

660

640

620

600

580

560

540

Bench Top RL

Tonn

es

02

46

81012

1416

1820

Gra

de %

Tonnes Zn % Pb %

BenchTop Tonnes Zn Pb Ag Zn_EqRL T % % % % Tonnage Metal840 2,279 14.43 7.83 9.17 20.69 114 24820 48,529 13.85 8.41 9.47 20.58 2,426 499800 150,405 13.99 8.24 10.33 20.58 7,520 1,547780 431,588 12.65 9.01 13.73 19.85 21,579 4,284760 388,349 11.57 9.65 17.82 19.29 19,417 3,746740 512,981 14.52 8.97 13.88 21.70 25,649 5,565720 785,421 16.76 10.09 12.52 24.83 39,271 9,752700 1,190,551 16.98 10.21 12.65 25.15 59,528 14,973680 1,057,487 17.64 10.34 13.60 25.92 52,874 13,704660 439,237 17.15 9.95 11.84 25.11 21,962 5,514640 848,624 16.94 10.77 11.96 25.57 42,431 10,848620 1,013,485 15.64 9.34 10.43 23.11 50,674 11,713600 571,838 14.86 8.37 9.38 21.55 28,592 6,163580 405,196 14.18 8.00 9.64 20.58 20,260 4,169560 124,869 13.52 7.52 9.53 19.54 6,243 1,220540 978 13.30 6.76 9.11 18.71 49 9

TOTAL 7,971,716 15.80 9.64 12.25 23.51 398,586 93,706

Per Vertical Metre


Total Measured, Indicated and Inferred Resource 5% Zn_Eq Cutoff

CutoffTonnes Zn_Eq % Grade Tonnes Zn_Eq %

0.0 to 5.0 207 5.0 7,971,923 23.515.0 to 7.5 1,788 7.92 7.5 7,971,716 23.527.5 to 10.0 29,649 10.13 10.0 7,969,928 23.52

10.0 to 12.5 178,904 11.42 12.5 7,940,279 23.5712.5 to 15.0 276,130 13.82 15.0 7,761,375 23.8515.0 to 17.5 472,039 16.35 17.5 7,485,244 24.2217.5 to 20.0 844,075 18.90 20.0 7,013,205 24.7520.0 to 22.5 1,359,643 21.34 22.5 6,169,130 25.5522.5 to 25.0 1,774,925 23.87 25.0 4,809,487 26.7425.0 to 27.5 1,583,480 26.13 27.5 3,034,562 28.4227.5 to 30.0 707,367 28.49 30.0 1,451,083 30.9230.0 to 999.0 743,716 33.23 999.0 743,716 33.23

7,971,923 23.51

Cumulative ResourceIncremental Resource

TOTAL


GradeRange

% Zn Eq

Anjing Hitam Deposit Grade Tonnage Curve

0 1,000,000 2,000,000 3,000,000 4,000,000 5,000,000 6,000,000 7,000,000 8,000,000 9,000,000

0 5 7.5 10 12.5 15 17.5 20 22.5 25 27.5 30

Zn Equiv Cutoff

Tonn

es

0

5

10

15

20

25

30

35

Gra

de %

Tonnes Zn_Equiv

Appendix 2


August 2004 Resource Validation Tables

APPENDIX 2 – RESOURCE VALIDATION TABLES

BenchTop Resource Zn Pb Number Volume Zn Pb Comp RatioRL Volume % % of comps Comps % % BCM/Comp840 588 14.43 7.83820 12,138 13.85 8.41 2 3,413 7.68 8.01 6,069800 36,031 13.99 8.24 27 46,070 13.80 8.31 1,334780 108,725 12.65 9.01 99 168,925 12.51 9.37 1,098760 100,375 11.57 9.65 76 129,680 9.20 8.87 1,321740 126,306 14.52 8.97 90 153,568 13.35 7.73 1,403720 182,144 16.76 10.08 93 158,687 16.45 9.99 1,959700 267,556 16.99 10.21 164 279,835 16.46 10.04 1,631680 244,506 17.64 10.34 109 185,988 17.08 10.34 2,243660 101,856 17.14 9.95 42 71,665 17.39 9.54 2,425640 194,219 16.94 10.78 130 221,821 16.03 9.98 1,494620 241,194 15.64 9.34 146 249,122 14.34 8.56 1,652600 138,688 14.86 8.36 60 102,379 14.55 7.35 2,311580 99,369 14.18 8.00 64 109,204 13.95 7.54 1,553560 31,506 13.52 7.52 3 5,119 8.92 5.69 10,502540 275 13.30 6.76

TOTAL 1,885,475 15.80 9.64 1,105 1,885,475 14.77 9.17 1,706

Composites


Comparison of Model and Composites by 20m Bench - All Zones

ALL ZONESBlock Model

Anjing Hitam Comparison of Model and Composites by 20m Bench - All Zones

0

50,000

100,000

150,000

200,000

250,000

300,000

840

820

800

780

760

740

720

700

680

660

640

620

600

580

560

540

Bench Top RL

Volu

mes

0.00

2.00

4.006.00

8.00

10.00

12.00

14.0016.00

18.00

20.00

Gra

de %


BenchTop Resource Zn Pb Number Volume Zn Pb Comp RatioRL Volume % % of comps Comps % % BCM/Comp840 588 14.43 7.83820 12,138 13.85 8.41 2 3,663 7.68 8.01 6,069800 36,000 13.99 8.24 27 49,453 13.80 8.31 1,333780 105,556 12.73 9.12 88 161,181 12.87 9.95 1,200760 92,269 11.82 10.03 72 131,876 9.39 9.16 1,282740 107,800 15.13 9.39 62 113,559 14.34 8.25 1,739720 171,431 17.12 10.34 79 144,697 17.59 10.78 2,170700 248,000 17.09 10.35 151 276,572 16.87 10.35 1,642680 241,706 17.67 10.37 104 190,487 17.42 10.64 2,324660 91,388 17.16 9.87 35 64,106 16.67 8.65 2,611640 171,206 17.33 11.06 102 186,824 17.03 10.57 1,678620 183,650 15.46 9.39 102 186,824 14.12 9.26 1,800600 126,750 14.81 8.41 47 86,085 15.43 7.97 2,697580 94,163 14.25 8.07 61 111,728 14.32 7.81 1,544560 27,800 13.70 7.61 2 3,663 5.03 3.24 13,900540 275 13.30 6.76

TOTAL 1,710,719 15.94 9.79 934 1,710,719 15.21 9.63 1,832

Composites


Comparison of Model and Composites by 20m Bench - MMH

MMHBlock Model

Anjing Hitam Comparison of Model and Composites by 20m Bench - MMH

0

50,000

100,000

150,000

200,000

250,000

300,000

840

820

800

780

760

740

720

700

680

660

640

620

600

580

560

540

Bench Top RL

Volu

mes

0.00

2.00

4.006.00

8.00

10.00

12.00

14.0016.00

18.00

20.00

Gra

de %


Northing Resource Zn Pb Number Volume Zn Pb Comp RatioVolume % % of comps Comps % % BCM/Comp

9475 6,094 15.30 9.40 8 13,650 15.69 10.14 7629500 33,763 16.67 9.85 24 40,951 15.87 8.27 1,4079525 40,513 17.00 10.51 16 27,301 14.12 7.69 2,5329550 35,413 16.31 10.54 24 40,951 17.09 12.06 1,4769575 67,100 15.93 10.30 58 98,966 14.23 9.09 1,1579600 68,469 15.62 9.77 33 56,308 15.70 8.75 2,0759625 75,000 16.04 9.88 9650 95,394 16.83 10.26 52 88,728 13.79 8.17 1,8349675 153,938 17.88 10.72 34 58,015 18.36 11.07 4,5289700 125,825 17.14 9.98 89 151,862 16.90 10.57 1,4149725 118,869 16.63 9.61 97 165,512 16.19 8.53 1,2259750 95,238 16.59 10.00 61 104,085 16.62 10.20 1,5619775 110,881 16.44 10.18 31 52,896 15.87 10.20 3,5779800 79,544 16.20 10.01 86 146,743 16.81 10.94 9259825 76,375 16.45 9.90 28 47,777 14.93 7.47 2,7289850 73,669 16.60 9.60 60 102,379 16.01 9.02 1,2289875 95,825 16.80 9.41 36 61,427 14.75 8.73 2,6629900 69,031 15.71 9.24 30 51,189 15.12 7.51 2,3019925 70,819 14.39 9.15 57 97,260 14.62 10.30 1,2429950 74,125 13.17 9.32 76 129,680 11.09 9.34 9759975 77,819 13.15 9.74 44 75,078 10.30 8.73 1,769

10000 38,981 12.67 8.55 25 42,658 12.04 7.05 1,55910025 46,219 11.75 7.34 26 44,364 10.19 7.36 1,77810050 37,344 11.98 7.61 62 105,791 12.64 7.69 60210075 36,038 13.96 8.21 10100 23,544 12.72 6.94 35 59,721 12.98 6.74 67310125 27,219 13.25 7.08 2 3,413 5.13 3.20 13,60910150 26,688 13.41 7.41 11 18,769 14.27 10.40 2,42610175 5,744 13.41 7.78 TOTAL 1,885,475 15.80 9.64 1,105 1,885,475 14.77 9.17 1,706

Composites


Comparison of Model and Composites by Northing- All Zones

ALL ZONESBlock Model

Anjing Hitam Comparison of Model and Composites by Northing - All Zones

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

160,000

180,000

9475

9500

9525

9550

9575

9600

9625

9650

9675

9700

9725

9750

9775

9800

9825

9850

9875

9900

9925

9950

9975

1000

0

1002

5

1005

0

1007

5

1010

0

1012

5

1015

0

1017

5

Northing

Vol

umes

0.002.004.006.008.0010.0012.0014.0016.0018.0020.00

Gra

de %


Northing Resource Zn Pb Number Volume Zn Pb Comp RatioVolume % % of comps Comps % % BCM/Comp

9475 6,094 15.30 9.40 9 16,864 13.67 7.94 6779500 33,763 16.67 9.85 24 44,971 17.09 12.06 1,4079525 40,513 17.00 10.51 47 88,069 15.34 10.27 8629550 34,788 16.43 10.66 33 61,836 15.70 8.75 1,0549575 64,000 16.19 10.58 9600 66,413 15.76 9.92 47 88,069 14.19 8.62 1,4139625 74,156 16.09 9.93 31 18.61 11.34 9650 92,175 16.98 10.41 73 136,788 18.03 11.43 1,2639675 150,719 17.98 10.81 75 140,535 17.40 9.72 2,0109700 112,081 17.65 10.39 61 114,302 16.62 10.20 1,8379725 105,694 17.13 10.01 23 43,098 16.29 10.49 4,5959750 91,788 16.68 10.03 83 155,526 16.38 10.56 1,1069775 106,388 16.48 10.17 19 35,602 16.05 7.55 5,5999800 74,194 16.07 9.84 60 112,428 16.01 9.02 1,2379825 71,650 16.56 9.94 28 52,467 16.88 9.94 2,5599850 69,756 16.95 9.80 30 56,214 15.12 7.51 2,3259875 93,219 16.99 9.50 51 95,564 15.37 10.94 1,8289900 67,938 15.79 9.29 76 142,409 11.09 9.34 8949925 69,000 14.49 9.23 36 67,457 10.86 9.46 1,9179950 69,594 13.13 9.43 13 24,359 15.04 9.68 5,3539975 65,813 12.88 10.04 7 13,117 4.21 8.05 9,402

10000 25,238 12.76 9.46 60 112,428 12.68 7.73 42110025 35,338 11.97 7.72 10050 35,013 12.17 7.77 35 65,583 12.98 6.74 1,00010075 35,981 13.96 8.22 2 5.13 3.20 10100 23,544 12.72 6.94 11 20,612 14.27 10.40 2,14010125 27,219 13.25 7.08 2 3,748 3.20 3.20 13,60910150 26,688 13.41 7.41 11 20,612 10.40 10.40 2,42610175 5,744 13.41 7.78 TOTAL 1,774,494 15.98 9.79 947 1,774,494 14.51 9.24 1,874

Composites


Comparison of Model and Composites by Northing- MMH

MMHBlock Model

Anjing Hitam Comparison of Model and Composites by Northing - MMH

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

160,000

180,000

9475

9500

9525

9550

9575

9600

9625

9650

9675

9700

9725

9750

9775

9800

9825

9850

9875

9900

9925

9950

9975

1000

0

1002

5

1005

0

1007

5

1010

0

1012

5

1015

0

1017

5

Northing

Vol

umes

0.002.004.006.008.0010.0012.0014.0016.0018.0020.00

Gra

de %


Appendix 3


August 2004 Resource Variography

APPENDIX 3 - VARIOGRAPHY

Zn Down hole

Zn 010o

Zn 100o dip -30 o

Pb Down hole

Pb 010 o

Pb 110 o -30 o Dip

Ag Down hole

Ag 010 o

Ag 110 o -30 o dip

Variogram Parameters for Dairi Main Zone

Nugget C1 A1 C2 A2 Variable: Zn Variance

Omnidirectional 1m Lag 3 9.3 3.5 26 23 Horizontal 010o 25m Lag 15 75 20.5 175

Down Dip -30o/100o 25m Lag 15 60 20.5 90 Relative Variance

Omnidirectional 1m Lag 8% 24% 3.5 68% 23 Horizontal 010o 25m Lag 39% 75 53% 175

Down Dip -30o/100o 25m Lag 39% 60 53% 90 Nugget C1 A1 C2 A2

Variable: Pb Variance Omnidirectional 1m Lag 5.3 8.7 3 18.5 9 Horizontal 010o 25m Lag 21 75 6.5 120

Down Dip -30o/100o 25m Lag 21 75 6.5 90 Relative Variance

Omnidirectional 1m Lag 16% 27% 3 57% 9 Horizontal 010o 25m Lag 64% 75 20% 120

Down Dip -30o/100o 25m Lag 64% 75 20% 90 Nugget C1 A1 C2 A2

Variable: Ag Variance Omnidirectional 1m Lag 20 41 3 105 13 Horizontal 010o 25m Lag 75 50 70 175

Down Dip -30o/100o 25m Lag 75 50 70 90 Relative Variance

Omnidirectional 1m Lag 12% 25% 3 63% 13 Horizontal 010o 25m Lag 45% 50 42% 175

Down Dip -30o/100o 25m Lag 45% 50 42% 90

Appendix 4


August 2004 Resource Surpac String File Definitions

APPENDIX 4 – SURPAC STRING FILE DEFINTIONS

(All relevant files are included on the Compact Disc inside the back cover of this report)

DIRECTORIES

3DMs • dairi_res804.dtm/dxf resource wireframe • footwall1.dtm/.dxf Julu footwall contact

BModel

• dairi0804.mdl resource block model • dair0804centroids.csv centroid dump of model • Macros.zip block model macros

Data

• Dairi3.mdb Access database for Anjing Hitam Reports & Spreadsheets

• Anjing Hitam Deposit August 2004 Resource Estimate.pdf -Resource report

• Anjing Hitam August 2004 Resource Tables.xls

-Resource tables Plots

• Blockmodelsections.zip -cross section files

The Anjing Hitam August 2004 mineral resource estimate was carried out using 3-D wireframes created in Surpac software with the ID2 block model being interpolated also using Surpac and the OK block model being interpolated using Datamine software.

resource evaluations pty ltdptdpm.co.id/id/images/stories/file/resource-evaluations...initially...

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