Surface Assays Increase Target Area at Big One

Castillo Copper Limited
07 October 2024
 

7 October 2024

 

CASTILLO COPPER LIMITED
("Castillo" or the "Company")

 

Surface Assays Increase Priority Copper Target Area at Big One Deposit

 

Castillo Copper Limited (LSE and ASX: CCZ), a base metal explorer primarily focused on copper across Australia and Zambia, is delighted with the findings from the recent surface sampling campaign which has increased the priority copper target area at the Big One Deposit proximal to the line of lode, historical workings and known orebody.

 

Highlights:

 

·    Completed a comprehensive surface sampling campaign at the Big One Deposit, within the NWQ Copper Project in the Mt Isa copper-belt, which delivered encouraging results and increased the target area:

Assayed surface samples (including rock chips up to 12% Cu) verified a significant anomaly that suggests copper mineralisation extends west along strike from historical workings and the known orebody

(Note: Big One Deposit Mineral Resource Estimate: 2.1Mt @ 1.1% Cu for 21,886t contained copper metal)1

Further, the assays indicated potential for copper mineralisation to extend south and to the east of the line of lode

Pleasingly, reconciling the new geochemical results with historical geophysical findings, validated known induced polarisation conductivity anomalies north of the line of lode

·    To gain further insights and geological understanding of the Big One Deposit, especially copper-bearing faulting trends, the field team completed a comprehensive mapping exercise

·    As a result, the geology team, post-reconciling the new geochemical inputs with legacy data, now has sufficient information to select priority targets for test-drilling that can potentially extend known mineralisation across an expanded area

 

Ged Hall, Chairman, commented: "The systematic surface sampling campaign around the Big One Deposit delivered encouraging results. Notably, the assays confirmed significant anomalous copper zones west of the known orebody, complemented with indications of incremental mineralisation to the south and east. Furthermore, completing a comprehensive mapping exercise has provided the geology team with deeper insights into localised copper-bearing faulting trends. Consequently, there are now more than sufficient data points to develop a comprehensive drilling campaign that has the potential to extend known mineralisation." 

 

ENLARGED PRIORITY COPPER TARGET AREA

 

Based on previous drilling campaigns and utilising historical data, the Big One Deposit's current MRE is 2.1Mt @ 1.1% Cu for 21,886t contained copper metal1.

 

The assayed surface samples, which include rock chips up to 12% Cu, verified a significant anomaly that suggests copper mineralisation extends west along strike from historical workings and the known orebody (Figure 1 and Appendix A-C). Furthermore, the assays suggest the potential for copper mineralisation to extend south and to the east of the line of lode.

 

Incrementally, the fresh geochemical results validated known induced polarisation conductivity anomalies that are north of the line of lode. 

 

FIGURE 1: ENLARGED COPPER TARGET AREA AT BIG ONE DEPOSIT

 

A map of a desert Description automatically generated

 

Source: CCZ geology team (Reference 2 and Appendix A)

 

As the field team were at the Big One Deposit for three days, they were able to complete a comprehensive mapping exercise to gain further insights and geological understanding of the copper-bearing faulting trends. 

 

Next Steps

 

Reconciling the new geochemical data from the surface sampling campaign with legacy information will enable the geology team to select viable targets to test-drill which have the potential to extend known mineralisation.

 

For further information, please contact:  

 

Castillo Copper Limited  

+61 8 6558 0886  

Gerrard Hall (UK), Chairman  

  

  

  

SI Capital Limited (Financial Adviser and Corporate Broker)  

+44 (0)1483 413500  

Nick Emerson  

   


   

Gracechurch Group (Financial PR)  

+44 (0)20 4582 3500

Harry Chathli, Alexis Gore, Henry Gamble 

  

 

 

References

 

1)    CCZ ASX Release - 28 February 2022

2)    Porter, M., 2024, Memo of Big One Field Inspection, Global Ore Discovery, unpublished report, August 2024, 33pp.

 

About Castillo Copper

 

Castillo Copper Limited is an Australian-based, Australian-focussed copper exploration Company with a strategy to develop multi-commodity assets that demonstrate future potential as an economic mining operation.

 

Through the application of disciplined and structured exploration and analysis, Castillo Copper has identified assets deemed core to the Company's sustained growth and is actively progressing these interests up the value curve.

 

Current focus will be on advancing exploration activity at the Company's wholly owned NWQ Project, situated in the copper-belt district approximately 150km north of Mt Isa in north-west Queensland.

 

Other interests include the Broken Hill Project in western New South Wales and the Cangai Copper Mine in north-east New South Wales, as well as exploration targets in Zambia.

 

Castillo Copper is listed on the LSE and ASX under the ticker "CCZ".

 

Competent Person's Statement

 

I, Mark Biggs, confirm that I am the Competent Person for the Competent Person Report from which the information to be publicly released has been obtained and confirm that:

·      I have read and understood the requirements of the 2012 Edition of the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (JORC Code, 2012 Edition) and the relevant sections of Chapter 5 and Guidance Note 31 from the ASX Listing Rules.

·      I am a Competent Person as defined by the JORC Code 2012 Edition, having 35 years of experience that is relevant to the copper mineralisation types, quality and potential mining method(s) of the deposit(s) described in the Report.  In addition, I have 21 years of experience in the estimation, assessment and evaluation of Exploration Results and Mineral Resource Estimates, the activity for which I am accepting responsibility.

•       I am a Member of The Australasian Institute of Mining and Metallurgy (Member # 107188).

·      I have reviewed the Report or Excerpt from the Report to which this Consent Statement applies.

·      I am a consultant working for ROM Resources and have been engaged by Castillo Copper Limited to prepare the documentation for the Big One Deposit on which the Report is based.

 

In addition:

·      I have disclosed to Castillo Copper Limited the full nature of the relationship between myself and the Company, including any issues that could be perceived by investors as a conflict of interest.  Mr Biggs is a director of ROM Resources, a company which is a shareholder of Castillo Copper Limited.  ROM Resources provides ad-hoc geological consultancy services to Castillo Copper Limited.

·      I verify that the Report is based on and fairly and accurately reflects in the form and context in which it appears, the information in my supporting documentation relating to Coal Resources.

I consent to the release of the Report and this Consent Statement by the Directors of Castillo Copper Limited.

APPENDIX A:  JORC CODE, 2012 EDITION - TABLE 1

 

The following JORC Code (2012 Edition) Table 1 is supplied to provide background for the recent geological mapping, soil, and rock chip sampling program at the 'Big One' Deposit, EPM 26574.

 

The reader of the current ASX Release is referred to the Castillo's other publications of the exploration results, diagrams, geological information, exploration planning activities and/or information contained in the body or appendices of the following Castillo ASX Releases:

 

·    "Field analysis verifies high-grade copper with newly identified gold mineralisation at Big One" released on the ASX by Castillo on the 14-Sep-2020.

·    "Plans underway to fully develop the big one deposit in the world-class Mt Isa copper belt", released on the ASX by Castillo on the 14-May-2024.

·    "Chief Geologist outlines plans for big one deposit surface sampling campaign", released on the ASX by Castillo on the 24-May-2024.

 

 


SECTION 1 SAMPLING TECHNIQUES AND DATA

 

Criteria

JORC Code explanation

Commentary

Sampling techniques

•    Nature and quality of sampling (e.g. cut channels, random chips, or specific specialised industry standard measurement tools appropriate to the minerals under investigation, such as down hole gamma sondes, or handheld XRF instruments, etc). These examples should not be taken as limiting the broad meaning of sampling.

•    Include reference to measures taken to ensure sample representivity and the appropriate calibration of any measurement tools or systems used.

•    Aspects of the determination of mineralisation that are Material to the Public Report.

•    In cases where 'industry standard' work has been done this would be relatively simple (e.g. 'reverse circulation drilling was used to obtain 1 m samples from which 3 kg was pulverised to produce a 30 g charge for fire assay'). In other cases, more explanation may be required, such as where there is coarse gold that has inherent sampling problems. Unusual commodities or mineralisation types (e.g. submarine nodules) may warrant disclosure of detailed information.

Rock Chip Samples - were collected from approximately a 3m radius around the recorded co-ordinate location. The rock chip fragments that were collected to make up the sample included fragments that approximately ranged from 2-5cm and 0.2 - 3kg in weight.  A total of 20 rock chip samples were collected in calico bags of which nine (9) were progressed for laboratory analysis (RB08900-909). Samples were collected from heaps that appeared to be unprocessed low-medium grade copper ore stockpiles. Samples of typical oxide (part supergene) mineralisation were sampled containing malachite, azurite, cuprite and chalcocite.

Soil Samples - These were collected from a reconnaissance survey orientated north-south with lines approximately 100m apart and sampling every 50m, located north and south of the mineralised trachyte dyke. A sub-set of twenty (20) of the samples collected were selected for laboratory analysis based on initial PXRF results.  As this was an orientation survey, the samples were sieved at -200 and -80 # mesh size for analysis.

Drilling techniques

•    Drill type (e.g. core, reverse circulation, open-hole hammer, rotary air blast, auger, Bangka, sonic, etc) and details (e.g. core diameter, triple or standard tube, depth of diamond tails, face sampling bit or other type, whether core is oriented and if so, by what method, etc).

Not Applicable - no exploration drilling results as none were drilled.

Drill sample recovery

•    Method of recording and assessing core and chip sample recoveries and results assessed.

•    Measures taken to maximise sample recovery and ensure representative nature of the samples.

•    Whether a relationship exists between sample recovery and grade and whether sample bias may have occurred due to preferential loss/gain of fine/coarse material.

Not Applicable - no exploration drilling results as none were drilled.

 

Logging

•    Whether core and chip samples have been geologically and geotechnically logged to a level of detail to support appropriate Mineral Resource estimation, mining studies and metallurgical studies.

•    Whether logging is qualitative or quantitative in nature. Core (or costean, channel, etc) photography.

•    The total length and percentage of the relevant intersections logged.

Descriptions of the rock chip samples are given in Appendix B of this CCZ's ASX Announcement dated the 30-Sep-2024.

Where appropriate strike and dip measurements were taken at an additional seven (7) sites, additional to the twenty (20) rock chip sample sites.

 

Subsampling techniques and sample preparation

•    If core, whether cut or sawn and whether quarter, half or all core taken.

•    If non-core, whether riffled, tube sampled, rotary split, etc and whether sampled wet or dry.

•    For all sample types, the nature, quality, and appropriateness of the sample preparation technique.

•    Quality control procedures adopted for all sub-sampling stages to maximise representivity of samples.

•    Measures taken to ensure that the sampling is representative of the in-situ material collected, including for instance results for field duplicate/second-half sampling.

•    Whether sample sizes are appropriate to the grain size of the material being sampled.

Of the sample collected about 0.3-2kg of rock chip and 30-60g of sieved soil samples were presented for analyses.

Assays were done by Independent Laboratory (ALS) with all samples initially crushed to 4 mm then pulverised to 75 microns, with at least 85% passing through 75 microns. Standard sample preparation and analyses procedures were performed on all samples and are considered appropriate techniques.

 

•    The nature, quality and appropriateness of the assaying and laboratory procedures used and whether the technique is considered partial or total.

•    For geophysical tools, spectrometers, handheld XRF instruments, etc, the parameters used in determining the analysis including instrument make and model, reading times, calibrations factors applied and their derivation, etc.

•    Nature of quality control procedures adopted (eg standards, blanks, duplicates, external laboratory checks) and whether acceptable levels of accuracy (ie lack of bias) and precision have been established. 

Assays were done by Independent Laboratory ALS at Mt Isa and Brisbane. All elements except for gold were analysed by method ME-MS61R (43 element testing via Aqua Regia digest then ICP-AES) and with many copper assays greater than 1%, the copper was redone using method Cu- OG46 with ICP-AES. All methods used were both suitable and appropriate for the styles of mineralisation present in the Big One Deposit.

The assay results were in line with previous rock chip and drilling results obtained since 2020 at Big One.

 

Verification of sampling and assaying

•    The verification of significant intersections by either independent or alternative company personnel.

•    The use of twinned holes.

•    Documentation of primary data, data entry procedures, data verification, data storage (physical and electronic) protocols.

•    Discuss any adjustment to assay data.

Independent Laboratory assaying by ALS has confirmed, within acceptable limits, the occurrences of high-grade copper inferred from the initial XRF readings. Laboratory standards and duplicates were used in accordance with standard procedures for geochemical assaying as noted below (Porter 2024):

Batch MI24236156

This batch has met the recommended insertion rates for the company QAQC controls (standards, blanks) with an overall insertion rate of 20%. However, no field duplicates were included in the batch and is recommended that 3% be included as detailed in the Table A1: Summary of QAQC insertion rates.

Both the company standards and blanks were verified for elements Cu, Co and Ag and returned results within two standard deviations (SD). Field duplicates are not present in the batch therefore were not reviewed.

Batch BR24245495

This batch has only met the recommended insertion rates for the company standards however no field duplicate and coarse blanks were included in the batch, blanks (Pulp) were inserted instead with an overall insertion rate of 10.5%.  It is recommended that 3% coarse blank and 3% field duplicates to be inserted as detailed in Table A1:  Summary of QAQC insertion rates.

Both the company standards and pulp blanks were verified for elements Cu, Co and Ag and returned results within two standard deviations (SD). Field duplicates and Coarse blanks are not present in the batch therefore were not reviewed.

Batch MI24241903

This batch has not met the recommended insertion rates for the company QAQC controls (standards, blanks, and field duplicates) however 10% pulp blanks were included in the batch. It is recommended that 4% standard, 3% Coarse blank and 3% field duplicate be included in a batch as detailed in the Table A1-. Summary of QAQC insertion rates.

The company pulp blanks were verified for elements Cu, Co and Ag and returned results within two standard deviations (SD). Standards, Field duplicates and Coarse blanks are not present in the batch therefore were not reviewed.  N.B please find the amended insertion rate table below.

Table A1:  Summary of QAQC insertion rates

A close-up of a table Description automatically generated

 

Location of data points

•    Accuracy and quality of surveys used to locate drill holes (collar and down-hole surveys), trenches, mine workings and other locations used in Mineral Resource estimation.

•    Specification of the grid system used.

•    Quality and adequacy of topographic control.

The spatial location for the rock chips and soils collected during this site visit at the Big One Deposit were collected by handheld GPS (-/+ 5m accuracy; MGA94 Zone54; Figure A1-1): The Table of rock chip locations and descriptions are in Appendix B.

 

Data spacing and distribution

•    Data spacing for reporting of Exploration Results.

•    Whether the data spacing, and distribution is sufficient to establish the degree of geological and grade continuity appropriate for the Mineral Resource and Ore Reserve estimation procedure(s) and classifications applied.

•    Whether sample compositing has been applied.

The spatial location for the photographs collected during the preliminary site visit at the Big One Deposit were collected at two previously mined sites that exposed the copper mineralisation, and across eight (8) previously identified anomalous areas. These anomalous areas were defined based on either historical rock chip sampling results or from conductivity anomalies described in the 2021 IP survey. Generally, the spacing of sampling and field observations varied between 50-200m to the north and south of the mineralised trachyte dyke.

Regional historical soil sample traverses indicated the Quilalar Formation carried the maximum copper grade which is 9 times the background. The basal dolomitic siltstones of the Lochness Formation had copper grades that were up to 4 times the background.  The copper geochemical response is interpreted as originating from either the faulted contact within the Quilalar units, or a local enrichment at the base of the carbonate lithologies.

 

Orientation of data in relation to geological structure

•    Whether the orientation of sampling achieves unbiased sampling of possible structures and the extent to which this is known, considering the deposit type.

•    If the relationship between the drilling orientation and the orientation of key mineralised structures is considered to have introduced a sampling bias, this should be assessed and reported if material.

In general, the strata of the area surrounding the trachyte dyke in the Quilalar and Lochness Formations dip mildly (5 to 30 degrees) to the north and strike between east to northeast.

Rock chip samples were taken at areas of interest from observed mineralisation along the line of lode of the mineralised dyke, secondary structures, surrounding spoil heaps, and across the eight (8) anomalous areas originally identified in the planning stage.

 

Sample security

•    The measures taken to ensure sample security.

The rock chip samples taken during the recent field trip were securely locked within the vehicle on site until delivered to Mt Isa for despatch to the laboratory (ALS) in person by the field personnel.

 

Audits or reviews

•    The results of any audits or reviews of sampling techniques and data.

The sampling techniques and the data generated from the laboratory assay results have been peer reviewed by consultant geologists familiar with the overall Big One Project and deemed to be acceptable.

Global Ore Discovery's (Porter 2024) field report has also provided an independent brief review of past findings and has made several recommendations for progressing the project forward.

 

 

Figure A1:  Location of Bedding Measurements and Rock Chip Sampling

A close-up of a map Description automatically generated



 

SECTION 2 REPORTING OF EXPLORATION RESULTS

(Criteria listed in the preceding section also apply to this section.)

Criteria

JORC Code explanation

Commentary

Mineral tenement and land tenure status

•    Type, reference name/number, location and ownership including agreements or material issues with third parties such as joint ventures, partnerships, overriding royalties, native title interests, historical sites, wilderness or national park and environmental settings.

•    The security of the tenure held at the time of reporting along with any known impediments to obtaining a licence to operate in the area. in the area.

The following mineral tenures are held 100% by subsidiaries of Castillo Copper Limited, totalling an area of 736.8 km2 in the "NWQ" Project which has QLD DOR Project Status (PROJ0221):

EPM 26574 (Valparaisa North) - encompasses the Big One historical mineral resource, Holder is Total Minerals Pty Ltd, Granted 12-June-2018 for a 5-year period over 100 sub-blocks (323.3Km2), Expires 11-June-2023 (Figure A1-2):

 

Figure A2:  Regional Project Location Map

A map with a location Description automatically generated

EPM 26462 (Big Oxide North) - encompasses the 'Boomerang' historical mine and the 'Big One' historical mine, Holder: QLD Commodities Pty Ltd, Granted: 29-Aug-2017 for a 5-year period over 67 sub-blocks (216.5Km2), Expires: 28-Aug-2022.

EPM 26525 (Hill of Grace) - encompasses the Ayra significant aeromagnetic anomaly, Holder: Total Minerals Pty Ltd for a 5-year period over 38 sub-blocks (128.8Km2), Granted: 12-June-2018, Expires: 11-June-2023.

EPM 26513 (Torpedo Creek/Alpha Project) - Granted 13-Aug-2018 for a 5-year period over 23 sub-blocks (74.2Km2), Expires 12-Aug-2023; and

EPM 27440 (The Wall) - An application lodged on the 12-Dec-2019 was granted on the 8-March-2021 over 70 sub-blocks (~215Km2) by Castillo Copper Limited. The tenure expires on the 8-March-2026.

A check on the tenures status was completed in 'GeoResGlobe' on the 23-September-2024, to validate the currentness of the exploration areas.

Exploration done by other parties

•    Acknowledgment and appraisal of exploration by other parties.

·      Historical QDEX / mineral exploration reports have been reviewed for historical tenures that cover or partially cover the Project Area in this announcement. Federal and State Government reports supplement the historical mineral exploration reporting (QDEX open file exploration records). Most explorers were searching for Cu-Au-U and proving satellite deposit style extensions to the several small subeconomic copper deposits (e.g. Big Oxide and Josephine).

·      With the NWQ Project in regional proximity to Mt Isa and numerous historical and active mines, the Project area has seen portions of the historical mineral tenure subject to various styles of surface sampling, with selected locations typically targeted by shallow drilling (Total hole depth is typically less than 50m).

The NWQ Project tenure package has a significant opportunity to be reviewed and explored by modern exploration methods in a coherent package of EPM's, with three of these forming a contiguous tenure package. Various Holders and related parties of the 'Big One' historical mining tenure (ML5814) completed a range of mining activities and exploration activities on what is now the 'Big One' prospect The following unpublished work is acknowledged (and previously shown in the reference list): 

West Australian Metals NL, 1994. Drill Programme at the "Big One" Copper Deposit, North Queensland for West Australian Metals NL.

Wilson, D., 2011. 'Big One' Copper Mine Lease 5481 Memorandum - dated 7 May 2011.

Wilson, D., 2015. 'Big One' Mining Lease Memorandum - dated 25 May 2015: and

Csar, M, 1996. Big One & Mt Storm Copper Deposits, unpublished field report.

The SRK Independent Geologists Report released by CCZ on the ASX on 28-July-2020 contains further details on the 'Exploration done by other parties - Acknowledgment and appraisal of exploration by other parties' this report is formally titled "A Competent Persons Report on the Mineral Assets of Castillo Copper Limited" Prepared as part of the Castillo Copper Limited (ASX: CCZ, LSE: CCZ) LSE Prospectus, with the effective date of the 17-July-2020. 

Geology

•    Deposit type, geological setting, and style of mineralisation.

The Mt Oxide North project is located within the Mt Isa Inlier of western Queensland, a large, exposed section of Proterozoic (2.5 billion- to 540-million-year-old) crustal rocks. The inlier records a long history of tectonic evolution, now thought to be like that of the Broken Hill Block in western New South Wales.

The NWQ Project lies within the Mt Oxide Domain, straddling the Lawn Hill Platform and Leichhardt River Fault Trough. The geology of the tenement is principally comprised of rocks of the Surprise Creek and Quilalar Formations which include feldspathic quartzites, conglomerates, arkosic grits, shales, siltstones and minor dolomites and limestones. T

The Project area is cut by a major fault zone, trending north- northeast - south- southwest across the permits. This fault is associated with major folding, forming several tight syncline-anticline structures along its length.

The Desktop studies commissioned by CCZ on the granted mineral tenures described four main styles of mineralisation account for most mineral resources within the rocks of the Mt Isa Province (after Withnall & Cranfield, 2013). 

Sediment hosted silver-lead-zinc - occurs mainly within fine-grained sedimentary rocks of the Isa Super basin within the Western Fold Belt. Deposits include Black Star (Mount Isa Pb-Zn), Century, George Fisher North, George.

Fisher South (Hilton) and Lady Loretta deposits: brecciated sediment hosted copper - occurs dominantly within the Leichhardt, Calvert, and Isa Super basin of the Western Fold Belt, hosted in brecciated dolomitic, carbonaceous, and pyritic sediments or brecciated rocks proximal to major fault/shear zones. Includes the Mount Isa copper orebodies and the Esperanza/Mammoth mineralisation. 

Iron-oxide-copper-gold ("IOCG") - predominantly chalcopyrite-pyrite magnetite/hematite mineralisation within high grade metamorphic rocks of the Eastern Fold Belt. Deposits of this style include Ernest Henry, Osborne, and Selwyn.

Broken Hill type silver-lead-zinc - occur within the high-grade metamorphic rocks of the Eastern Fold Belt. Cannington is the major example, but several smaller currently sub-economic deposits are known.

Gold is primarily found associated with copper within the IOCG deposits of the Eastern Fold Belt. However, a significant exception is noted at Tick Hill where high grade gold mineralisation was produced, between 1991 and 1995 by Carpentaria Gold Pty Ltd, some 700,000 tonnes of ore was mined at an average grade of 22.5 g/t Au, producing 15,900 kg Au. The Tick Hill deposit style is poorly understood (Withnall & Cranfield, 2013).

ROM Resources had noted in a series of recent reports for CCZ on the granted tenures, that cover the known mineralisation styles including:

Stratabound copper mineralisation within ferruginous sandstones and siltstones of the Surprise Creek Formation. 

Disseminated copper associated with trachyte dykes.

Copper-rich iron stones (possible IOCG) in E-W fault zones.

Possible Mississippi Valley Type ("MVT") stockwork sulphide mineralisation carrying anomalous copper-lead, zinc, and silver. 

The Mt Oxide and Mt Gordon occurrences are thought to be breccia and replacement zones with interconnecting faults. The Mt Gordon/Mammoth deposit is hosted by brittle quartzites, and Esperanza by carbonaceous shales. Mineralisation has been related to the Isan Orogeny (1,590 - 1,500 Ma).

Mineralisation at all deposits is primarily chalcopyrite-pyrite-chalcocite, typically as massive sulphide within breccias associated with a NE trending fault (062o to 242o) that is intruded by a porphyry dyke.

Other observations are:

The mineralised porphyry dyke is vertical to near vertical (85o), with the 'true width' dimensions reaching up to 9m at surface.

At least 600m in strike length, with strong Malachite staining observed along the entire strike length, with historical open pits having targeted approximately 200m of this strike. Exact depth of mining below the original ground surface is not clear in the historical documents, given the pits are not battered it is anticipated that excavations have reached 5m to 10m beneath the original ground surface.

Associated with the porphyry dyke are zones of fractured and/or sheared rock, the siltstones are described as brecciated, and sandstones around the shear as carbonaceous.

The known mineralisation from the exploration activities to date had identified shallow supergene mineralisation, with a few drill-holes targeting deeper mineralisation in and around the 800m of strike, with the mineralisation still open to the east, north, and downdip.

A strongly altered hanging wall that contained malachite and cuprite nodules. Chalcocite mineralisation has been identified but it is unclear on the prevalence of the Chalcocite.

The mineralisation was amenable to high grade open pit mining methods of the oxide mineralization (as indicated by numerous historical open pit shallow workings into the shear zone).

Desktop studies commissioned by CCZ and completed by ROM Resources and SRK Exploration have determined that the Big One prospect is prospective for Cu, Co, and Ag.

Drillhole Information

•    A summary of all information material to the understanding of the exploration results including a tabulation of the following information for all Material drill holes: o easting and northing of the drill hole collar

o    elevation or RL (Reduced Level - elevation above sea level in metres) of the drill hole collar

o    dip and azimuth of the hole o down hole length and interception depth o hole length.

•    If the exclusion of this information is justified on the basis that the information is not Material and this exclusion does not detract from the understanding of the report, the Competent Person should clearly explain why this is the case.

Not Applicable - no exploration drilling results presented.

Data aggregation methods

•    In reporting Exploration Results, weighting averaging techniques, maximum and/or minimum grade truncations (e.g. cutting of high grades) and cut-off grades are usually Material and should be stated.

•    Where aggregate intercepts incorporate short lengths of high-grade results and longer lengths of low-grade results, the procedure used for such aggregation should be stated and some typical examples of such aggregations should be shown in detail.

•    The assumptions used for any reporting of metal equivalent values should be clearly stated.

Independent Laboratory Assay results for the 9 rock chip and 20 soil samples from the Big One Deposit were averaged if more than one reading or determination was given. There was no cutting of high-grade copper results as they are directly relatable to high grade mineralisation styles readily visible in the relevant samples. Results are presented in Appendices B and C.

There were no cut-off grades factored into any reporting of the laboratory assay results.

Relationship between mineralisation widths and intercept lengths

•    These relationships are particularly important in the reporting of Exploration Results.

•    If the geometry of the mineralisation with respect to the drill hole angle is known, its nature should be reported.

•    If it is not known and only the down hole lengths are reported, there should be a clear statement to this effect (e.g. 'down hole length, true width not known').

Rock chip samples were taken at areas of interest from observed mineralisation along the line of lode of the mineralised dyke, secondary structures, and surrounding identified anomalous mapping areas..  Eight (8) rock chip samples collected from rock faces and/or outcrops.

Sampling was generally designed to cover targets identified from previous surface sampling and/or the ground IP geophysical survey

Diagrams

•    Appropriate maps and sections (with scales) and tabulations of intercepts should be included for any significant discovery being reported These should include, but not be limited to a plan view of drill hole collar locations and appropriate sectional views.

Appropriate diagrams are presented in the body and the Appendices of the current ASX Release. Where scales are absent from the diagram, grids have been included and clearly labelled to act as a scale for distance. 

Maps and Plans presented in the current ASX Release are in MGA94 Zone 54, Eastings (mN), and Northing (mN), unless clearly labelled otherwise.

Balanced reporting

•    Where comprehensive reporting of all Exploration Results is not practicable, representative reporting of both low and high grades and/or widths should be practiced avoiding misleading reporting of Exploration Results.

Rock chip samples were taken at areas of interest from observed mineralisation along the line of lode of the mineralised dyke, secondary structures, surrounding spoil heaps, and to the north and south of the line of lode to check the validity of the defined eight (8) anomalous map areas. 

Other Substantial Exploration Data

•    Other exploration data, if meaningful and material, should be reported including (but not limited to): geological observations; geophysical survey results; geochemical survey results; bulk samples - size and method of treatment; metallurgical test results; bulk density, groundwater, geotechnical and rock characteristics; potential deleterious or contaminating substances.

The area is covered by regional airborne government and private radiometric, gravity, magnetic, and hyperspectral surveys. Unfortunately, other than the 2021 IP ground survey, no other ground surveys have been undertaken.

Substantial historical and current ground geochemical (stream sediment, soil, and rock chip samples have been undertaken and three episodes of drilling since 1970 completed.

Further work

•    The nature and scale of planned further work (e.g. tests for lateral extensions or depth extensions or large-scale step-out drilling).

•    Diagrams clearly highlighting the areas of possible extensions, including the main geological interpretations and future drilling areas, provided this information is not commercially sensitive.

The following recommendations were made in Porter (2024):

A  major focus should be on structural mapping - the mineralisation is structurally controlled.

Identify and map access to top of the ridge should drilling from northern ridge be necessary.

Soils - expand soil sampling grid once assay/pXRF orientation data studied see Figure A1-3).

Gravity - given the structural nature of the mineralisation, a small ground gravity program is justified. The survey should show up the structures and lithology contrasts well, allowing a drilling campaign to proceed with the necessary groundwork being completed to give Castillo the best chance of hitting and reporting significant economic mineralisation.

 



 

Figure A3:  Soil Sample locations and PXRF Results of Size Fractions

A map of a desert Description automatically generated

Modified after Porter (2024)


APPENDIX B: MAPPING AND SAMPLE DATA

 

Dip Dir

Dip

Strike

Easting

Northing

Feature

Lthcode

Description

deg

Deg

deg

GDA94

GDA94




30.5

10

120.5

335582

7880358

Bedding

QT

Quartzite

31.5

25

121.5

335592

7880358

Bedding Contact

QT

Quartzite

365.5

29

455.5

335596

7880398

Bedding

IS

Haematitic Sandstone

26.5

40

116.5

335603

7880409

Bedding

IS

Haematitic Sandstone

27.5

14

117.5

335689

7880507

Bedding

SS

Sandstone

30.5

20

120.5

335580

7880575

Bedding

SS

Sandstone

355.5

9

445.5

335504

7880403

Bedding

ST

Siltstone

 

Source: CCZ geology team

 

Sample_ID

Easting

Northing

RL

Lithology

Alt_Type

Alt_Int

Alt_Style

Comments

LAB

ORDER#

Cu ppm_pxrf

Co ppm_pxrf

Ag ppm_pxrf

RB08900

335446

7880420

171

Trachyte with Malachite




Malachite  - material almost certainly ejecta from pit - not insitu

ALS

MI24236156

290988

108

61

RB08901

335551

7880319

162

Sandstone

He

W

Pat

Proximal to contact with southern quartzite

ALS

MI24236156

53



RB08902

335549

7880316

181

Quartzite




Fine grained - meta siltstone. Trace bedding visible

ALS

MI24236156

11



RB08903

335582

7880361

183

Quartzite

He

S

Fr

Fractured quartzite with haematitic fault gauge

ALS

MI24236156

20



RB08904

335588

7880369

182

Sandstone

He

S

Per

haematitic sandstone

ALS

MI24236156

30



RB08905

335596

7880383

182

Sandstone

He

S

Per

haematitic sandstone - gossanous textures developing. Sub-cropping on steep hill

ALS

MI24236156

191



RB08906

335593

7880397

181

Sandstone

He

S

Per

haematitic sandstone - Mn surface staining in places

ALS

MI24236156

159



RB08907

335327

7880582

182

Sandstone

He

S

Per

haematitic sandstone - gossanous textures developing. 

ALS

MI24236156

107



RB08908

335302

7880550

183

quartzite

He

S

Per

haematitic quartzite

ALS

MI24236156

18



RB08909

335667

7880499

207

Ant Hill sample




Ant Hill sample

ALS

MI24236156

63



RB08912

335508

7880542

207

Sandstone - partly brecciated

He

W

pat

Brecciated /conglomeritic sandstone, weakly he stained.



33



RB08913

335499

7880546

212

Sandstone

He

W

pat

haematitic sandstone



31



RB08914

335472

7880597

208

quartzite

He

W

pat

Weakly haematitic



23



RB08915

335361

7880590

212

Sandstone

He

S

Per

haematitic sandstone



18



RB08916

335341

7880558

193

Sandstone

He

S

Per

haematitic sandstone



5



RB08917

335318

7880563

182

Sandstone

He

M

Per

haematitic sandstone - Mn surface staining in places



5

94


RB08918

335312

7880563

183

haematitic sandstone

He

S

per

He sandstone



21



RB08919

335443

7880412

168

trachyte with Malachite




Malachite on fracture surfaces in trachyte - not insitu, most likely ejecta



418711

116

48

RB08920

335464

7880367

186

Malachite, haematitic sandstone, fractured, intrusive contact

Malachite, azurite, mine stockpile above pit



189519

231


RB08921

335504

7880400

172

Malachite, haematitic ironstone, fractured, trachyte

He

S

Per

Fault contact - trachyte / haematitic sandstone



23200

538


 

Source: CCZ geology team



 

APPENDIX C:  LABORATORY ASSAY RESULTS

 

SiteID

Samp_#

X

Y

Z

Company

Locality

From

To

Thick

TYPE

Cu_Pxrf_ppm

Lithcode

Rock Description

RB08900

RB08900

335446.0

7880420.0

171.0

CCZ-GOD

Big One

0

1

1

RC

290988

TR

Malachite  - material almost certainly ejecta from pit - not insitu

RB08901

RB08901

335551.0

7880319.0

162.0

CCZ-GOD

Big One

0

1

1

RC

53

SS

Proximal to contact with southern quartzite

RB08902

RB08902

335549.0

7880316.0

181.0

CCZ-GOD

Big One

0

1

1

RC

11

QT

Fine grained - meta siltstone. Trace bedding visible

RB08903

RB08903

335582.0

7880361.0

183.0

CCZ-GOD

Big One

0

1

1

RC

20

QT

Fractured quartzite with haematitic fault gauge

RB08904

RB08904

335588.0

7880369.0

182.0

CCZ-GOD

Big One

0

1

1

RC

30

SS

haematitic sandstone

RB08905

RB08905

335596.0

7880383.0

182.0

CCZ-GOD

Big One

0

1

1

RC

191

SS

haematitic sandstone - gossanous textures developing. Sub cropping on steep hill

RB08906

RB08906

335593.0

7880397.0

181.0

CCZ-GOD

Big One

0

1

1

RC

159

SS

haematitic sandstone - Mn surface staining in places

RB08907

RB08907

335327.0

7880582.0

182.0

CCZ-GOD

Big One

0

1

1

RC

107

SS

haematitic sandstone - gossanous textures developing. 

RB08908

RB08908

335302.0

7880550.0

183.0

CCZ-GOD

Big One

0

1

1

RC

18

QT

haematitic quartzite

RB08909

RB08909

335667.0

7880499.0

207.0

CCZ-GOD

Big One

0

1

1

RC

63

SO

Ant Hill sample

RB08912

RB08912

335508.0

7880542.0

207.0

CCZ-GOD

Big One

0

1

1

RC

33

SS

Brecciated /conglomeritic sst, weakly he stained.

RB08913

RB08913

335499.0

7880546.0

212.0

CCZ-GOD

Big One

0

1

1

RC

31

SS

haematitic sandstone

RB08914

RB08914

335472.0

7880597.0

208.0

CCZ-GOD

Big One

0

1

1

RC

23

QT

Weakly haematitic

RB08915

RB08915

335361.0

7880590.0

212.0

CCZ-GOD

Big One

0

1

1

RC

18

SS

haematitic sandstone

RB08916

RB08916

335341.0

7880558.0

193.0

CCZ-GOD

Big One

0

1

1

RC

5

SS

haematitic sandstone

RB08917

RB08917

335318.0

7880563.0

182.0

CCZ-GOD

Big One

0

1

1

RC

5

SS

haematitic sandstone - Mn surface staining in places

RB08918

RB08918

335312.0

7880563.0

183.0

CCZ-GOD

Big One

0

1

1

RC

21

IS

He sandstone

RB08919

RB08919

335443.0

7880412.0

168.0

CCZ-GOD

Big One

0

1

1

RC

418711

TR

Malachite on fracture surfaces in trachyte - not insitu, most likely ejecta

RB08920

RB08920

335464.0

7880367.0

186.0

CCZ-GOD

Big One

0

1

1

RC

189519

SS

Malachite, azurite, mine stockpile above pit

RB08921

RB08921

335504.0

7880400.0

172.0

CCZ-GOD

Big One

0

1

1

RC

23200

TR

Fault contact - trachyte / haematitic sandstone

SB05472

SB05472

334749.9

7880044.4


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

29

SO


SB05473

SB05473

334951.0

7880144.6


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

122

SO


SB05474

SB05474

334952.7

7880094.9


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

87

SO


SB05475

SB05475

334949.4

7880047.7


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

56

SO


SB05476

SB05476

335047.9

7880398.7


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

69

SO


SB05477

SB05477

335049.6

7880346.5


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

42

SO


SB05478

SB05478

335047.9

7880297.7


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

27

SO


SB05479

SB05479

335051.2

7880248.9


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

70

SO


SB05480

SB05480

335051.2

7880195.1


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

69

SO


SB05481

SB05481

335151.4

7880496.4


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

32

SO


SB05481

SB05481_Duplicate

335151.4

7880496.4


CCZ-GOD

Big One



0.3

SOIL -80µm


SO


SB05482

SB05482

335153.0

7880445.9


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

178

SO


SB05483

SB05483

335152.2

7880398.7


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

80

SO


SB05484

SB05484

335150.5

7880347.4


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

135

SO


SB05485

SB05485

335153.9

7880293.6


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

116

SO


SB05486

SB05486

335153.0

7880246.4


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

317

SO


SB05487

SB05487

335149.7

7880199.2


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

15

SO


SB05488

SB05488

335153.0

7880145.4


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

20

SO


SB05489

SB05489

335148.9

7880099.0


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

15

SO


SB05490

SB05490

335350.0

7880197.5


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

30

SO


SB05491

SB05491

335352.5

7880149.5


CCZ-GOD

Big One

0.2

0.5

0.3

SOIL -80µm

81

SO


Source: CCZ geology team



 

SiteID

Ag

As

Ba

Ce

Co

Cr

Cu

Fe

La

Mn

P

Pb

Sb

Th

Y

Zn

Nd

Pr

 

ppm

ppm

ppm

ppm

ppm

ppm

ppm

%

ppm

ppm

ppm

ppm

ppm

ppm

ppm

ppm

ppm

ppm

RB08900

3.04

128

310

2.05

21.6

341

120000

0.62

0.8

17

280

3.4

435

0.6

3.6

7

1.9

0.36

RB08901

<0.01

5.2

300

149.5

3.6

25

20.9

1.62

95.5

151

310

2.6

0.56

22.1

26.1

17

60.6

18.05

RB08902

0.02

2.4

150

28

1.9

12

154.5

0.81

17

56

90

1.9

1.25

4.83

4.5

6

9.8

3.12

RB08903

0.01

0.8

180

38.3

0.9

15

9.4

0.61

17

56

100

2.9

0.77

9.71

14.6

3

14.8

4.04

RB08904

<0.01

22.7

110

39.3

3.5

10

30.6

1.55

18.4

191

120

2.5

1.36

7.2

12.9

9

13.8

4.06

RB08905

0.02

16.4

620

60.1

31.4

25

185

19.25

35.2

3030

3250

9.5

8.67

21.1

39.8

79

24

7.24

RB08906

0.01

7.9

3100

62.5

109.5

21

236

6.2

31.3

18300

660

10.4

7.9

20.9

31.4

138

21.3

6.03

RB08907

0.01

4.4

720

29.8

8.8

20

46.2

4.08

14.6

2800

130

8.5

1.51

17.05

12.6

12

7

2.16

RB08908

0.01

1.6

330

45.2

8.1

11

14.4

2.49

20.3

3160

150

5.8

1.08

10

21.2

11

16.4

4.52

RB08909

0.08

20.8

150

91.5

3.9

58

55

1.59

48

207

200

9.6

4.19

13.75

22

10

36.2

11.15

SB05472

<0.01

0.5

<10

2.94

0.4

5

4.7

0.34

1.4

37

10

1

0.15

0.8

0.7

3

1.2

0.34

SB05473

0.01

3.8

520

72.8

9.8

32

20.7

2.28

37.6

1085

210

14.2

1.02

13.4

25.7

18

33.2

9.15

SB05474

0.01

13

510

73.1

18.4

63

125

3.86

38.2

1160

660

14.6

1.99

15.95

24.7

36

31.5

9.25

SB05475

0.02

5.8

410

102.5

11.9

50

42.9

3.89

52.2

857

590

13.6

2.05

21.6

29.1

36

44.2

12.35

SB05476

0.03

5.9

530

98.2

17.8

44

27.5

3.72

49.2

3280

410

14.6

1.62

19.8

38

35

44.1

12.1

SB05477

<0.01

3.8

500

93.3

12.4

41

12.2

2.94

49.9

1470

240

14.2

1.37

18.7

29

22

43.7

12.1

SB05478

0.02

6.1

500

82.3

12.2

41

90.7

2.86

41.2

2090

270

12.3

1.16

17.55

33.1

17

35.8

9.92

SB05479

0.02

5.6

450

72.2

15

49

76.1

2.59

31.3

2020

200

12

0.97

14.25

24.6

16

28.4

7.84

SB05480

0.01

3.5

520

67.9

10.6

28

14.2

2.11

31.7

1130

180

12.4

0.94

11.75

21.3

15

26.8

7.68

SB05481

0.01

4.2

570

107

15

44

16.4

3.03

53.9

1595

290

15

1.32

20.5

33.4

26

47.9

13.6

SB05481

0.01

3.9

570

96.4

14.3

42

15.9

3.04

50

1600

290

14.6

1.28

19.35

32.6

25

44.3

12.15

SB05482

0.06

8.8

430

75.5

17

73

486

3.93

40.1

2830

320

11.1

1.28

17.9

35.2

16

36.3

10.1

SB05483

0.02

6.4

500

91.7

17.2

38

20.7

3.02

40.1

2720

270

15.3

1.3

17.15

29.6

18

34.3

9.71

SB05484

<0.01

5.1

490

84.1

16.2

36

20.3

2.99

38.8

1785

260

14.9

1.12

16.25

27.4

18

32.7

9.28

SB05485

0.01

6.9

670

112.5

18.6

46

23

3.78

53.6

1915

380

15.7

1.68

18.95

30.6

23

44.9

12.85

SB05486

0.01

7.4

680

113.5

22.7

38

14.6

3.23

47.9

3630

460

13.8

1.47

20.1

40.3

19

44.6

12.15

SB05487

0.02

4.5

480

79.1

12.5

42

36.5

3.97

41.8

2650

390

11

1.2

21.3

38.5

23

37.1

10.3

SB05488

0.03

8

460

86.6

13.2

43

135.5

3.11

44.1

2270

310

11.7

1.16

17.85

33.4

17

40.6

11.1

SB05489

0.02

7.3

450

69.5

8.9

29

159.5

1.98

32.9

668

220

12.2

2.12

13.9

26.8

11

28.9

8.09

SB05490

0.02

6.6

640

76.9

11.6

34

110.5

2.4

38.9

1470

360

11.6

1.54

16.7

27.7

19

34

9.47

SB05491

0.02

5.3

630

89.7

13.1

40

136

3.17

43.3

2250

390

12.8

1.23

20.8

45.8

27

40.8

10.85

Source: CCZ geology team

Notes:

1.        ALS Reporting details discussed in JORC Table 1

2.        Table shows selected results from method ME-MS61R

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