REG - Castillo Copper Ltd - Contractors appointed to spearhead BHA campaign
31/08/2022 07:00
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RNS Number : 6679X Castillo Copper Limited 31 August 2022
31 August 2022
CASTILLO COPPER LIMITED
("Castillo" or the "Company")
Contractors appointed to spearhead Broken Hill campaign; REE potential
Castillo Copper Limited (LSE and ASX: CCZ), a base metal explorer primarily
focused on copper across Australia and Zambia, is pleased to announce it has
appointed two contractors for the upcoming drilling campaign at the BHA
Project's East Zone.
HIGHLIGHTS
· With the inaugural drilling campaign expected to commence at the BHA
Project's East Zone in the fourth quarter, subject to regulatory approval from
the NSW Resources Regulator, the Board has made two key contractor
appointments:
o AllState Drilling's(1) team will perform the campaign(2) which comprises one
diamond core and 17 RC drill-holes for 2,100m, with depths from 100m to 160m;
and
o FieldCrew(3), which has performed work at the NWQ Copper Project in
Queensland, will manage the day-to-day aspects of the drilling campaign
· Post-announcing, Australia secured preferred status for the supply of
critical minerals to the US's electric vehicle battery program(4), the Board
wants to deepen its understanding of the East Zone's Rare Earth Element (REE)
potential at two targets:
o The Sisters Prospect: both planned RC drill-holes will be analysed for
copper-cobalt-gold and REEs(2)
o Iron Blow: having already confirmed the presence of REEs(5), the geology
team is targeting to test additional drill-core samples from the core library
to determine if there are further extensions to known mineralisation
Dr Dennis Jensen, Managing Director of Castillo Copper, commented: "The Board
is delighted to have secured AllState and FieldCrew as key contractors for the
upcoming drilling campaign. Notably, AllState is a highly reputable drilling
group, while FieldCrew has done considerable fieldwork across the BHA and NWQ
Copper Projects. In addition, with sentiment currently positive towards REEs,
the Board is interested in boosting its understanding of the potential across
The Sisters and Iron Blow Projects."
FIGURE 1: PROPOSED DRILLING CAMPAIGN BHA PROJECT EAST ZONE
Prospects # Drillholes Target Commodity Depth range (m) Type Objective
Reefs Tank, Tors Tank, Fence Gossan 16 Co, Au, Ag, Cu 100-160 15 RC, 1 DDH Target primary cobalt whilst assays to investigate PGE & REE potential
The Sisters 2 Co, Cu, REE 120-160 2 RC Test known EM interpretation; drill extensions north & south
Source: CCZ geology team
REE potential
Following the announcement that Australia has secured preferred status to
supply critical minerals to the US's electric vehicle battery program(4), the
Board decided it prudent to deepen its understanding of the REE potential
within the East Zone at The Sisters and Iron Blow Prospects.
Currently, two drill-holes are planned for The Sisters Prospect(2) - both will
be assayed for REEs along with cobalt-copper and gold.
Previous assays of historic drill-core have already confirmed REE
mineralisation apparent at the Iron Blow Prospect:
8m @ 1,270ppm Total Rare Earth Oxides from 150m (DD90-IB3)(5)
For further information, please contact:
Castillo Copper Limited +61 8 6558 0886
Dr Dennis Jensen (Australia), Managing Director
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 3488 7510
Harry Chathli, Alexis Gore
About Castillo Copper
Castillo Copper Limited is an Australian-based explorer primarily focused on
copper across Australia and Zambia. The group is embarking on a strategic
transformation to morph into a mid-tier copper group underpinned by its core
projects:
· A large footprint in the Mt Isa copper-belt district, north-west
Queensland, which delivers significant exploration upside through having
several high-grade targets and a sizeable untested anomaly within its
boundaries in a copper-rich region.
· Four high-quality prospective assets across Zambia's copper-belt
which is the second largest copper producer in Africa.
· A large tenure footprint proximal to Broken Hill's world-class
deposit that is prospective for zinc-silver-lead-copper-gold and platinoids.
· Cangai Copper Mine in northern New South Wales, which is one of
Australia's highest grading historic copper mines.
The group is listed on the LSE and ASX under the ticker "CCZ."
Competent Person's Statement
The information in this report that relates to Exploration Results and Mineral
Resource Estimates for "BHA Project, East Zone" is based on information
compiled or reviewed by Mr Mark Biggs. 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. Mr Biggs is a member of the Australian Institute of Mining and
Metallurgy (member #107188) and has sufficient experience of relevance to the
styles of mineralisation and types of deposits under consideration, and to the
activities undertaken, to qualify as a Competent Person as defined in the 2012
Edition of the Joint Ore Reserves Committee (JORC) Australasian Code for
Reporting of Exploration Results, and Mineral Resources. Mr Biggs holds an
AusIMM Online Course Certificate in 2012 JORC Code Reporting. Mr Biggs also
consents to the inclusion in this report of the matters based on information
in the form and context in which it appears.
References
1) AllState Drilling. Available at:
https://www.allstatedrilling.com.au/
2) CCZ ASX Release - 9 August 2022
3) FieldCrew. Available at: https://www.fieldcrew.com.au/
4) "Australia's critical minerals to drive USA's EV battery
program" Available at:
https://www.minerals.org.au/news/australia%E2%80%99s-critical-minerals-drive-usas-ev-battery-program
5) CCZ ASX Release - 5 May 2022
APPENDIX A: PROSPECTS IN BHA PROJECT'S EAST ZONE
FIGURE A1: PROSPECTS AT BHA PROJECT EAST ZONE
Source: CCZ geology team
FIGURE A2: BHA PROJECT
Source: CCZ geology team
APPENDIX B: PLANNED DRILLING CAMPAIGN
FIGURE B1: PLANNED DRILLING AT FENCE GOSSAN, REFF & TORS TANK PROSPECTS
SiteID Area E N AHD TD AZI DIPV DIPH Source Type
2022_FG_01 Fence Gossan 576550 6453790 169.52 120 180 30 -60 CCZ RC
2022_FG_03 Fence Gossan 576550 6453755 169.008 120 180 30 -60 CCZ RC
2022_FG_04 Fence Gossan 576350 6453790 172.774 120 180 30 -60 CCZ RC
2022_FG_07 Fence Gossan 576700 6453835 170.65 160 180 30 -60 CCZ RC
2022_FG_08 Fence Gossan 574120 6453255 180.774 130 180 30 -60 CCZ RC
2022_FG_09 Fence Gossan 573325 6453175 189.137 130 170 30 -60 CCZ RC
2022_RT_01 Reef Tank 574105 6456245 183.699 120 180 30 -60 CCZ RC
2022_RT_02 Reef Tank 574120 6455475 188.494 120 180 30 -60 CCZ RC
2022_RT_03 Reef Tank 573725 6454930 188.616 120 180 30 -60 CCZ RC
2022_RT_07 Reef Tank 574575 6455405 188.634 120 180 30 -60 CCZ RC
2022_TT_01 Tors Tank 571231 6451499 194.025 120 180 30 -60 CCZ RC
2022_TT_02 Tors Tank 571359 6451402 192.373 100 180 30 -60 CCZ RC
2022_TT_03 Tors Tank 571425 6451280 188.743 120 180 30 -60 CCZ RC
2022_TT_04 Tors Tank 571475 6451250 188.064 100 180 30 -60 CCZ RC
2022_TT_07 Tors Tank 571585 6451245 187.012 120 180 30 -60 CCZ RC
Note: One of the RC drillholes will be twinned with an HQ or BQ diamond cored
hole to obtain core for a variety of testing.
FIGURE B2: PLANNED DRILLING AT THE SISTERS PROSPECT
BoreID Area E N AHD TD AZI DIPV DIPH Source Type
2022_TS_06 The Sisters 566526 6481011 280 160 100 25 -65 CCZ RC
2022_TS_13 The Sisters 566701 6480017 280 120 100 25 -65 CCZ RC
Source: CCZ geology team
FIGURE B3: LOCATION OF PROPOSED DRILL-HOLES
Source: CCZ geology team
FIGURE B4: LOCATION OF PROPOSED HOLES
Source: CCZ geology team
APPENDIX C: JORC CODE, 2012 EDITION - TABLE
Section 1 Sampling Techniques and Data
Criteria JORC Code explanation Commentary
Sampling techniques · Nature and quality of sampling (e.g., cut channels, random chips, Diamond Drilling (DDH)
or specific specialised industry standard measurement tools appropriate to the
minerals under investigation, such as down hole gamma sondes, or handheld XRF · Pre-1990: Diamond drilling was used to obtain core from which
instruments, etc.). These examples should not be taken as limiting the broad irregular intervals, reflecting visual mineralisation and geological logging
meaning of sampling. were hand-split or sawn. Samples were submitted for analysis using a mixed
acid digestion and AAS methodology.
· Include reference to measures taken to ensure sample
representivity and the appropriate calibration of any measurement tools or · Post-1990: Diamond drilling was used to obtain core from which
systems used. irregular intervals, reflecting visual mineralisation and geological logging
were sawn (quarter core for HQ). Samples were submitted for analysis using a
· Aspects of the determination of mineralisation that are Material mixed acid digestion and ICP-OES methodology.
to the Public Report.
· 2002 - 2022 (including the core library reanalysis holes):
· In cases where 'industry standard' work has been done this would Diamond drilling will be used to obtain core from which irregular intervals
be relatively simple (e.g., 'reverse circulation drilling was used to obtain 1 were sawn with one half core to be dispatched for assay by mixed acid
m samples from which 3 kg was pulverised to produce a 30g charge for fire digestion and analysis via ICP-MS + ICP-AES reporting a suite of 48 elements
assay'). In other cases, more explanation may be required, such as where there (sulphur >10% by LECO; gold by fire assay). The remaining sample (core)
is coarse gold that has inherent sampling problems. Unusual commodities or was retained for future metallurgical test work (in progress) and archival
mineralisation types (eg submarine nodules) may warrant disclosure of detailed purposes.
information.
Reverse Circulation ('RC') Drilling
· Pre-2017 RC drilling was used to obtain a representative sample
by means of riffle splitting with samples submitted for analysis using the
above-mentioned methodologies.
· Pre-2000 drill samples were assayed for a small and variable
suite of elements (but NBH holes included cobalt). The post-2000 drill
samples are all assayed by ICP-MS for a suite of 33 elements.
· 2000-2022 RC drilling was used to obtain a representative sample
by means of a cone or riffle splitter with samples submitted for assay by
mixed acid digestion and analysis via ICP-MS + ICP-AES reporting a suite of 48
elements (sulphur >10% by LECO; gold by fire assay).
Re-Analysis of GSNSW Core
· Regarding the six (6) historical cored holes held by the NSW
Geological Survey across EL 8434 and 8435, selected sections that were
originally re-analysed using pXRF analyzer have been cut by diamond saw for
laboratory analysis. This work recovered one hundred and eighty-four (184)
samples, each about 1m in length (of HQ, BQ, and NQ drill core) which were
retested by ALS Brisbane, using ME-MS61R and PGM-ICP27 methods.
· Quarter core was submitted to ALS for chemical analysis using
industry standard sample preparation and analytical techniques.
· Half core was also collected for metallurgical testwork from BH1,
the results from which are
· The sample interval details and grades quoted for cored intervals
described in various maps in the main section are given in Appendix C at the
end of this section.
Drilling techniques · Drill type (e.g., core, reverse circulation, open-hole hammer, · Historical drilling consists of auger, rotary air blast, reverse
rotary air blast, auger, Bangka, sonic, etc.) and details (e.g. core diameter, circulation, and NQ, BQ, and HQ diamond coring.
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.). · Diamond drilling was predominantly completed with standard
diameter, conventional HQ and NQ with historical holes typically utilizing RC
and percussion pre-collars to an average 30 metres (see Drill hole Information
for further details)
· Early (1970 -1980): drill holes utilised HX - AX diameters
dependent on drilling depth. Reverse circulation drilling utilised standard
hole diameters (4.8"-5.5") with a face sampling hammer.
· Since 2000 all diamond drilling has been completed using a triple
tube system with an NQ3 - HQ3 diameter. Drill holes were typically drilled at
angles between 40 and 60 degrees from horizontal and
· The resulting core was oriented as part of the logging process.
In and around The Sisters model area are twelve (12) drillholes, however it
should be noted that the majority of these are <50m in depth, and the
number of holes >100m number only numbers 4 holes.
Drill sample recovery · Method of recording and assessing core and chip sample recoveries · Reverse Circulation ('RC') Drilling - Reverse circulation sample
and results assessed. recoveries will be visually estimated during drilling programs. Where the
estimated sample recovery is below 100% this will be recorded in field logs by
· Measures taken to maximise sample recovery and ensure means of qualitative observation.
representative nature of the samples.
· Reverse circulation drilling will employ sufficient air (using a
· Whether a relationship exists between sample recovery and grade compressor and booster) to maximise sample recovery.
and whether sample bias may have occurred due to preferential loss/gain of
fine/coarse material. · No relationship between sample recovery and grade has been
observed during historical drilling campaigns.
Logging · Whether core and chip samples have been geologically and · The drilling that did occur historically was generally completed
geotechnically logged to a level of detail to support appropriate Mineral to modern-day standards. The preferred exploration strategy in the eighties
Resource estimation, mining studies and metallurgical studies. and early nineties was to drill shallow auger holes to negate the influence of
any Quaternary and Tertiary sedimentary cover, and then return to sites where
· Whether logging is qualitative or quantitative in nature. Core anomalous Cu or Zn were assayed.
(or costean, channel, etc) photography.
· No downhole geophysical logging is planned; however, measurements
· The total length and percentage of the relevant intersections of magnetic susceptibility will be taken over the same intervals as the PXRF
logged. readings are planned to be taken.
Sub-sampling techniques and sample preparation · If core, whether cut or sawn and whether quarter, half or all · It is considered water to be used for core cutting is unprocessed
core taken. and unlikely to have introduce significant sample contamination.
· If non-core, whether riffled, tube sampled, rotary split, etc and · Procedures relating to the definition of the line of cutting or
whether sampled wet or dry. splitting are not available. It is expected that 'standard industry
practice' for the period was applied to maximize sample representivity.
· For all sample types, the nature, quality, and appropriateness of
the sample preparation technique. · Half core is planned to be submitted to ALS for chemical analysis
using industry standard sample preparation and analytical techniques.
· Quality control procedures adopted for all sub-sampling stages to
maximise representivity of samples. · Half core will also be collected and composited from the cored
holes for further metallurgical testwork from BH1, where preliminary results
· Measures taken to ensure that the sampling is representative of reported to the ASX on 2(nd) August 2022.
the in-situ material collected, including for instance results for field
duplicate/second-half sampling. · The sample interval details and grades quoted for cored intervals
described in various maps in the main section are given in previous ASX
· Whether sample sizes are appropriate to the grain size of the releases (Castillo Copper 2022a, b, c, d, e, f).
material being sampled.
Quality of assay data and laboratory tests · The nature, quality and appropriateness of the assaying and · The nature and quality of all assaying and laboratory procedures
laboratory procedures used and whether the technique is considered partial or employed for samples obtained through drilling (diamond and reverse
total. circulation) are considered 'industry standard' for the respective periods.
· For geophysical tools, spectrometers, handheld XRF instruments, · The assay techniques employed for drilling (diamond and reverse
etc, the parameters used in determining the analysis including instrument make circulation) include mixed acid digestion with ICP-OES, ICP-AES, ICP-MS and
and model, reading times, calibrations factors applied and their derivation, AAS finishes. These methods are considered appropriate for the targeted
etc. mineralisation and regarded as a 'near total' digestion technique with
resistive phases not expected to affect cobalt analysis. using ME-MS61R and
· Nature of quality control procedures adopted (eg standards, PGM-ICP27 methods.
blanks, duplicates, external laboratory checks) and whether acceptable levels
of accuracy (i.e. lack of bias) and precision have been established. · All samples have been contracted to be processed at independent
commercial laboratory Australian Laboratory Services, (ALS).
· For the laboratory inserted standards, blanks and duplicates were
analysed per industry standard practice. There was no evidence of bias from
these results.
· None of the drillholes have been twinned, as they are historical
holes.
· To monitor the accuracy of assay results from drilling, CRM
standards were included in the assay sample stream at an average rate of 1:24.
Internal lab standards were routinely included by ALS Brisbane for the
proposed CCZ testing.
Verification of sampling and assaying · The verification of significant intersections by either · Historical drilling intersections were internally verified by
independent or alternative company personnel. personnel employed by previous explorers including CRAE Pty Limited,
Falconbridge Limited and Hunter Resources. North Broken Hill Pty Ltd and
· The use of twinned holes. EagleHawk Consulting completed a systematic review of the related data.
· Documentation of primary data, data entry procedures, data · The CCZ drilling database exists in electronic form under the
verification, data storage (physical and electronic) protocols. independent management of ROM Resources. The database procedures strictly
apply integrity rules to all downhole and measurement recordings. If data
· Discuss any adjustment to assay data. fails the integrity rules, the data is not loaded into the database.
· Historical drilling data available in electronic form has been
re-formatted and imported into the drilling database. Quantitative
historical drilling data, including assays, have been captured electronically
during systematic data compilation and validation completed by ROM
Resources. Assay results from the new proposed drilling will be added to
this database.
· Samples returning assays below detection limits are assigned half
detection limit values in the database.
· All significant intersections are verified by CCZ's Exploration
Manager.
Location of data points · Accuracy and quality of surveys used to locate drill holes · The holes, once drilled, are planned to be surveyed by DGPS in
(collar and down-hole surveys), trenches, mine workings and other locations projection MGA94 (Zone 54).
used in Mineral Resource estimation.
· It is estimated that locational accuracy therefore varies between
· Specification of the grid system used. 0.1-0.5m.
· Quality and adequacy of topographic control. · The quality of topographic control (GSNSW 1 sec DEM) is deemed
adequate for the purposes of the Mineral Resource estimate.
Data spacing and distribution · Data spacing for reporting of Exploration Results. · Detailed geological mapping is supported by drill-hole data of
sufficient spacing and distribution to allow updating of the existing 3D
· Whether the data spacing and distribution is sufficient to geological modelling and Mineral Resource estimation.
establish the degree of geological and grade continuity appropriate for the
Mineral Resource and Ore Reserve estimation procedure(s) and classifications · The current drilling program generally has holes placed at 250m
applied. spacing.
· Whether sample compositing has been applied. · The average sample spacing across the tenure varies per element,
and sample type, as listed in Table C-1, below:
Table C-1: EL 8434 and EL 8435 Surface and Drillhole Sampling
Description Number Average Spacing Comments
Stream Sediment 1,395 320 Includes BCL
Soil 1,049 240
Surface Rock Chip 2,150 185
Drilling 6,346 220 Includes shallow auger holes. Six (6) holes in the tenures are held in GSNSW
library.
Mineral Occurrences 98 420 Includes quarries and industrial minerals occurrences
· The average sample spacing across the tenure varies per prospect,
and sample type, as listed in Table C-2, below:
Table C-2: EL 8434 and EL 8435 Drillhole Spacing
Prospect Drillholes in Model RMS Drillhole Spacing (m)
The Sisters 12 242
Iron Blow 8 315
Tors Tank 342 27.4
Fence Gossan 549 25.5
Ziggy's Hill 245 37.0
Reefs Tank 1,375 22.1
· The Datamine software allows creation of fixed length samples
from the original database given a set of stringent rules.
Orientation of data in relation to geological structure · Whether the orientation of sampling achieves unbiased sampling of · The planned drill holes at BHAE are designed to be angled at
possible structures and the extent to which this is known, considering the -55˚ or -60˚ to the horizontal and drilled perpendicular to the mineralised
deposit type. trend for RC and DDH (Figure 4 in the main body text).
· If the relationship between the drilling orientation and the · The drilling orientation is not considered to have introduced a
orientation of key mineralised structures is considered to have introduced a sampling bias on assessment of the current geological interpretation.
sampling bias, this should be assessed and reported if material.
· Geological mapping by various companies has reinforced that the
strata dips variously between 5 and 65 degrees.
Sample security · The measures taken to ensure sample security. · The sample security measures will be dictated by Fieldcrew field
procedure, who will take samples to their Broken Hill office and transported
samples for analysis to ALS Brisbane
Audits or reviews · The results of any audits or reviews of sampling techniques and · No external audits or reviews have yet been undertaken.
data.
· The average sample spacing across the tenure varies per prospect,
and sample type, as listed in Table C-2, below:
Table C-2: EL 8434 and EL 8435 Drillhole Spacing
Prospect Drillholes in Model RMS Drillhole Spacing (m)
The Sisters 12 242
Iron Blow 8 315
Tors Tank 342 27.4
Fence Gossan 549 25.5
Ziggy's Hill 245 37.0
Reefs Tank 1,375 22.1
· The Datamine software allows creation of fixed length samples
from the original database given a set of stringent rules.
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.
· The planned drill holes at BHAE are designed to be angled at
-55˚ or -60˚ to the horizontal and drilled perpendicular to the mineralised
trend for RC and DDH (Figure 4 in the main body text).
· The drilling orientation is not considered to have introduced a
sampling bias on assessment of the current geological interpretation.
· Geological mapping by various companies has reinforced that the
strata dips variously between 5 and 65 degrees.
Sample security
· The measures taken to ensure sample security.
· The sample security measures will be dictated by Fieldcrew field
procedure, who will take samples to their Broken Hill office and transported
samples for analysis to ALS Brisbane
Audits or reviews
· The results of any audits or reviews of sampling techniques and
data.
· No external audits or reviews have yet been undertaken.
BHAE Drilling Program Notes
The BHAE drill program includes 17 RC drill-holes with combined depth of
2,100m, and one diamond core to be completed with a HQ or NQ core barrel and
will have a combined depth of 100m, of which approximately 90m will be
cored. Drill-hole depths range from 70m to 160m. Azimuths vary to
intersect cobalt-rich horizons perpendicular to strike, where the drill-hole
inclination will range from 60(O) to 65(O).
The drill-holes are particularly designed to penetrate deep enough to
intersect the two lower cobalt-rich zones ("CO3" and "CO4"). Horizon "CO3"
is interpreted to contain higher cobalt values than those modelled to date
(Figure C1).
The drilling program will be conducted on privately held ground. Access
arrangements will be in place. The drilling contractor will need to abide by
any conditions set out in the access arrangements. These conditions will be
communicated prior to exploration commencing.
Access to drill sites will be via pre-existing tracks and temporary access
tracks. Castillo will provide detailed access maps to the drilling
contractor. Preliminary maps have been provided in Figures C2-C4 and in
Appendix A & B.
Two RC samples per metre are to be collected per metre drilled; one bulk
sample to be placed in a large, pre-numbered plastic bag; and a second 5kg,
riffle split sub-sample to be placed in a pre-numbered calico bag.
Drill core is to be orientated and placed in core trays. The drilling
contractor will be required to conduct drillhole orientation survey in all 17
drill-holes and conduct multi-shot survey at the interval of 30m in
drill-holes whose depth exceeds 50m.
The cored hole location is yet to be decided but will be a twin of a drilled
RC hole. The cored hole is important as it will provide:
· Core for possible hyperspectral scanning, and detailed
geological logging.
· Samples for thin section and petrological description.
· Detailed assay information.
· Core for specific gravity testing.
· Core for geotechnical testing.
· Core for further detailed metallurgical testing.
FIGURE C-1: FENCE GOSSAN, TYPICAL ROCK TYPES AND SAMPLING INTERVALS
INTERSECTED DURING DRILLING
Source: CCZ geology team
FIGURE C-2: TORS TANK, PROPOSED DRILLING PROGRAM
Source: CCZ geology team
FIGURE C-3: REEFS TANK, PROPOSED DRILLING PROGRAM
Source: CCZ geology team
FIGURE C-4: FENCE GOSSAN, PROPOSED DRILLING PROGRAM
Source: CCZ geology team
SECTION 2 REPORTING OF EXPLORATION RESULTS
Criteria JORC Code explanation Commentary
Mineral tenement and land tenure status · Type, reference name/number, location and ownership including EL 8434 is located about 28km east of Broken Hill whilst EL 8435 is 16km east
agreements or material issues with third parties such as joint ventures, of Broken Hill. Both tenures are approximately 900km northwest of Sydney in
partnerships, overriding royalties, native title interests, historical sites, far western New South Wales (Figure A1-2-1).
wilderness or national park and environmental settings.
EL 8434 and EL 8435 were both granted on the 2(nd of) June 2016 to Squadron
· The security of the tenure held at the time of reporting along Resources for a term of five (5) years for Group One Minerals. On the 25(th
with any known impediments to obtaining a licence to operate in the area. of) May 2020, Squadron Resources changed its name to Wyloo Metals Pty Ltd
(Wyloo). In December 2020 the tenure was transferred from Wyloo Metals to
Broken Hill Alliance Pty Ltd a 100% subsidiary company of Castillo Copper
Limited. Both tenures were renewed on the 12(th of) August 2021 for a
further six (6) years and are due to expire on the 2(nd of) June 2027.
EL 8434 lies across two (2) 1:100,000 geology map sheets Redan 7233 and
Taltingan 7234, and two (2) 1:250,000 geology map sheets, SI54-3 Menindee, and
SH54-15 Broken Hill in the county of Yancowinna. EL 8434 consists of one
hundred and eighty-six (186) units) in the Adelaide and Broken Hill
1:1,000,000 Blocks covering an area of approximately 580km(2).
EL 8435 is located on the 1:100,000 geology map sheet Taltingan 7234, and the
1:250,000 geology map sheet SH/54-15 Broken Hill in the county of
Yancowinna. EL 8435 consists of twenty-two (22) units (Table 1) in the
Broken Hill 1:1,000,000 Blocks covering an area of approximately 68km(2).
Access to the tenures from Broken Hill is via the sealed Barrier Highway.
This road runs north-east to south-west through the northern portion of the EL
8434, passes the southern tip of EL 8435 eastern section and through the
middle of the western section of EL 8435. Access is also available via the
Menindee Road which runs north-west to south-east through the southern section
of the EL 8434. The Orange to Broken Hill Rail line also dissects EL 8435
western section the middle and then travels north-west to south-east slicing
through the eastern arm of EL 8434 (Figure C-2).
Figure C-2: EL 8434 and EL 8435 General Location Map
Exploration done by other parties · Acknowledgment and appraisal of exploration by other parties. Explorers who were actively involved over longer historical periods in various
parts of EL8434 were: - North Broken Hill Ltd, CRAE Exploration, Major Mining
Ltd and Broken Hill Metals NL, Pasminco Exploration Ltd, Normandy Exploration
Ltd, PlatSearch NL/Inco Ltd/ EGC Pty Ltd JV and the Western Plains Gold
Ltd/PlatSearch/EGC Pty Ltd JV.
A comprehensive summary of work by previous explorers was presented in Leyh
(2009). However, more recently, follow-up field reconnaissance of areas of
geological interest, including most of the prospective zones was carried out
by EGC Pty Ltd over the various licenses. This work, in conjunction with a
detailed interpretation of aeromagnetic, gravity plus RAB / RC drill hole
logging originally led to the identification of at least sixteen higher
priority prospect areas. All these prospects were summarized in considerable
detail in Leyh (2008). Future work programs were then also proposed for each
area. Since then, further compilation work plus detailed geological
reconnaissance mapping and sampling of gossans and lode rocks has been carried
out.
A total of 22 prospects were then recognised on the exploration licence with
at least 12 occurring in and around the tenure.
With less than 45% outcropping Proterozoic terrain within the licence, this
makes it very difficult to explore and is in the main very effectively
screened from the easy application of more conventional exploration
methodologies due to a predominance of extensive Cainozoic cover sequences.
These include recent to young Quaternary soils, sands, clays and older more
resistant, only partially dissected, Tertiary duricrust regolith covered
areas. Depth of cover ranges from a few metres in the north to over 60
metres in some areas on the southern and central license.
Exploration by EGC Pty Ltd carried out in the field in the first instance has
therefore been heavily reliant upon time consuming systematic geological
reconnaissance mapping and relatable geochemical sampling. These involve a
slow systematic search over low outcropping areas, poorly exposed subcrops and
float areas as well as the progressive development of effective regolith
mapping and sampling tools. This work has been combined with a vast amount
of intermittently acquired past exploration data. The recent data
compilation includes an insufficiently detailed NSWGS regional mapping scale
given the problems involved, plus some regionally extensive, highly variable,
low-level stream and soil BLEG geochemical data sets over much of the area.
There are also a few useful local detailed mapping grids at the higher
priority prospects, and many more numerous widespread regional augers, RAB,
and percussion grid drilling data sets. Geophysical data sets including ground
magnetics, IP and EM over some prospect areas have also been integrated into
the exploration models. These are located mainly in former areas of moderate
interest and most of the electrical survey methods to date in this type of
terrain continue to be of limited application due to the high degree of
weathering and the often prevailing and complex regolith cover constraints.
Between 2007 and 2014 Eaglehawk Geological Consulting has carried out detailed
research, plus compilation and interpretation of a very large volume of
historic exploration data sourced from numerous previous explorers and dating
back to the early 1970's. Most of this data is in non-digital scanned form.
Many hard copy exploration reports (see references) plus several hundred plans
have been acquired from various sources, hard copy printed as well as
downloaded as scans from the Geological Survey of NSW DIGS system. They also
conducted field mapping, costean mapping and sampling, and rock chip sampling
and analysis.
Work Carried out by Squadron Resources and Whyloo Metals 2016-2020
Research during Year 1 by Squadron Resources revealed that the PGE-rich,
sulphide-bearing ultramafic rocks in the Broken Hill region have a
demonstrably alkaline affinity. This indicates a poor prospectivity for
economic accumulations of sulphide on an empirical basis (e.g., in comparison
to all known economic magmatic nickel sulphide deposits, which have a
dominantly tholeiitic affinity). Squadron instead directed efforts toward
detecting new Broken Hill-Type (BHT) deposits that are synchronous with basin
formation. Supporting this modified exploration rationale are the EL's
stratigraphic position, proximity to the Broken Hill line of lode, abundant
mapped alteration (e.g., gahnite and/or garnet bearing exhalative units) and
known occurrences such as the "Sisters" and "Iron Blow" prospects.
The area overlies a potential magmatic Ni-Cu-PGE source region of
metasomatised sub-continental lithospheric mantle (SCLM) identified from a
regional targeting geophysical data base. The exploration model at the time
proposed involved remobilization of Ni-Cu-PGE in SCLM and incorporation into
low degree mafic-ultramafic partial melts during a post-Paleoproterozoic plume
event and emplacement higher in the crust as chonoliths/small intrusives -
Voisey's Bay type model. Programs were devised to use geophysics and
geological mapping to locate secondary structures likely to control and
localise emplacement of Ni-Cu-PGE bearing chonoliths. Since EL8434 was
granted, the following has been completed:
• Airborne EM survey.
• Soil and chip sampling.
• Data compilation.
• Geological and logistical reconnaissance.
• Community consultations; and
• Execution of land access agreements.
Airborne EM Survey
Geotech Airborne Limited was engaged to conduct an airborne EM survey using
their proprietary VTEM system in 2017. A total of 648.92-line kilometres
were flown on a nominal 200m line spacing over a portion of the project area.
Several areas were infilled to 100m line spacing.
The VTEM data was interpreted by Southern Geoscience Consultants Pty Ltd, who
identified a series of anomalies, which were classified as high or low
priority based on anomaly strength (i.e., does the anomaly persist into the
latest channels). Additionally, a cluster of VTEM anomalies at the "Sisters"
prospect have been classified separate due to strong IP effects observed in
the data. Geotech Airborne have provided an IP corrected data and
interpretation of the data has since been undertaken.
Soil and Chip sampling
The VTEM anomalies were followed up by a reconnaissance soil sampling
programme. Spatially clustered VTEM anomalies were grouped, and follow-up soil
lines were designed. Two (2) VTEM anomalies were found to be related to
culture and consequently no soils were collected. Two (2) other anomalies
were sampled which were located above thick alluvium of Stephens Creek and
were therefore not sampled. A line of soil samples was collected over a
relatively undisturbed section at Iron Blow workings and the Sisters Prospect.
One hundred and sixty-six (166) soil samples were collected at a nominal 20cm
depth using a 2mm aluminum sieve. Two (2) rock chips were also collected
during this program. The samples were collected at either 20m or 40m spacing
over selected VTEM anomalies. The samples were pulverised and analysed by
portal XRF at ALS laboratories in Perth.
Each site was annotated with a "Regolith Regime" such that samples from a
depositional environment could be distinguished from those on exposed
Proterozoic bedrock, which were classified as an erosional environment. The
Regolith Regime groups were used for statistical analysis and levelling of the
results. The levelled data reveals strong relative anomalies in zinc at VTEM
anomaly clusters 10, 12 and 14 plus strong anomalous copper at VTEM 17.
Geology · Deposit type, geological setting, and style of mineralisation. Regional Geology
The Broken Hill polymetallic deposits are located within Curnamona Province
(Willyama Super group) (Figure C-3) that hosts several world-class deposits of
lead, zinc, silver, and copper. The Willyama Supergroup consists of highly
deformed metasedimentary schists and gneisses with abundant quartz-feldspathic
gneisses, lesser basic gneisses, and minor 'lode' rocks which are
quartz-albite and calc-silicate rocks (Geoscience Australia, 2019). Prograde
metamorphism ranges from andalusite through sillimanite to granulite grade
(Stevens, Barnes, Brown, Stroud, & Willis, 1988).
Regionally, the tenures are situated in Broken Hill spatial domain which
extends from far western New South Wales into eastern South Australia. The
Broken Hill Domain hosts several major fault systems and shear zones, which
were formed by various deformation events and widespread metamorphism which
has affected the Willyama Supergroup (Figure C-4).
Major faults in the region include the Mundi Mundi Fault to the west of Broken
Hill, the Mulculca Fault to the east, and the Redan Fault to the south. Broken
Hill is also surrounded by extensive shear zones including the Stephens Creek,
Globe-Vauxhall, Rupee, Pine Creek, Albert, and Thackaringa-Pinnacles Shear
Zones.
Figure C-3: Regional Stratigraphy
Modified after: (Stevens, Barnes, Brown, Stroud, & Willis, 1988)
Figure C-4: Regional Geological Map
Modified after (Peljo, 2003)
Local Geology
There are over twenty (20) rock formations mapped within the project area.
Parts of the project area are covered by Quaternary alluvium, sands, and by
Tertiary laterite obscuring the basement geology. Within the Lower to Middle
Proterozoic Willyama Supergroup (previously Complex) there are two (2) groups,
the Thackaringa Group, and the younger Broken Hill Group (Colquhoun, et al.,
2019). A summary of the units that host or appear to host the various
mineralisation styles within EL 8434 and EL 8435 is given below.
Broken Hill Group
The Hores Gneiss is mostly comprised of quartz-feldspar-biotite-garnet gneiss,
interpreted as metadacite with some minor metasediments noted. An age range
from Zircon dating has been reported as 1682-1695Ma (Geoscience Australia,
2019). The Allendale Metasediments unit contains mostly metasedimentary
rocks, dominated by albitic, pelitic to psammitic composite gneiss, including
garnet-bearing feldspathic composite gneiss, sporadic basic gneiss, and
quartz-gahnite rock. Calc-silicate bodies can be found at the base of the
unit and the formation's average age is 1691 Ma (Geoscience Australia, 2019).
Thackaringa Group
The Thorndale Composite Gneiss is distinguished by mostly gneiss, but also
migmatite, amphibolite, and minor magnetite. The age of this unit is
>1700Ma (Geoscience Australia, 2019) and is one of the oldest formations in
the Group. The Cues Formation is interpreted as a deformed sill-like
granite, including Potosi-type gneiss. Other rock-types include pelitic
paragneiss, containing cordierite. The average age: ca 1700-1730 Ma.
(Stevens, Barnes, Brown, Stroud, & Willis, 1988). Other rock types
include mainly psammo-pelitic to psammitic composite gneisses or
metasedimentary rocks, and intercalated bodies of basic gneiss. This unit is
characterised by stratiform horizons of granular garnet-quartz +/-magnetite
rocks, quartz-iron oxide/sulphide rocks and quartz-magnetite rocks (Geoscience
Australia, 2019). This is a significant formation as it hosts the Pinnacles
Ag-Pb-Zn massive sulphide deposit along with widespread Fe-rich stratiform
horizons.
The protolith was probably sandy marine shelf sedimentary rocks. An
intrusion under shallow cover was syn-depositional. The contained
leuco-gneisses and Potosi-type gneisses are believed to represent a felsic
volcanic or volcaniclastic protolith. Basic gneisses occur in a substantial
continuous interval in the middle sections of the Formation, underlain by
thinner, less continuous bodies. They are moderately Fe-rich (abundant
orthopyroxene or garnet) and finely layered, in places with pale feldspar-rich
layers, and are associated with medium-grained quartz-feldspar-biotite-garnet
gneiss or rock which occurs in thin bodies or pods ('Potosi-type' gneiss).
A distinctive leucocratic quartz-microcline-albite(-garnet) gneiss
(interpreted as meta-rhyolite) occurs as thin, continuous, and extensive
horizons, in several areas. The sulphide-bearing rocks may be lateral
equivalents of, or associates of Broken Hill type stratiform mineralisation.
Minor layered garnet-epidote-quartz calc-silicate rocks occur locally within
the middle to basal section. The unit is overlain by the Himalaya
Formation.
The Cues Formation is intruded by Alma Granite (Geoscience Australia, 2019).
The Himalaya Formation (Figure C-6) consists of medium-grained saccharoidal
leucocratic psammitic and albitic meta-sedimentary rocks (average age
1700Ma). The unit comprises variably interbedded albite-quartz rich rocks,
composite gneiss, basic gneiss, horizons of thinly bedded quartz-magnetite
rock.
Pyrite-rich rocks occur at the base of the formation (Geoscience Australia,
2019). It is overlain by the Allendale Metasediments (Broken Hill Group).
The Himalaya Formation hosts cobalt-rich pyritic horizons at Pyrite Hill and
Big Hill. The protolith is probably sandy marine shelf sedimentary rocks
with variable evaporitic or hypersaline component. Plagioclase-quartz rocks
are well-bedded (beds 20 - 30mm thick), with rare scour-and-fill and
cross-bedded structures.
Thin to thick (0.5 - 10m) horizons of thinly bedded quartz-magnetite rock also
occur with the plagioclase-quartz rocks. In some areas the formation
consists of thin interbeds of plagioclase-quartz rocks within meta-sedimentary
rocks or metasedimentary composite gneiss (Geoscience Australia, 2019). Lady
Brassey Formation which is well-to-poorly-bedded leucocratic sodic
plagioclase-quartz rock, as massive units or as thick to thin interbeds within
psammitic to pelitic metasedimentary composite gneisses. A substantial
conformable basic gneiss. It overlies both Mulculca Formation and Thorndale
Composite Gneiss. Part of the formation was formerly referred to as Farmcote
Gneiss in the Redan geophysical zone of Broken Hill Domain - a zone in which
the stratigraphy has been revised to create the new Rantyga Group (Redan and
Ednas Gneisses, Mulculca Formation, and the now formalised Farmcote Gneiss).
Lady Louise Suite
This unit is approximately 1.69Ma in age comprising amphibolite,
quartz-bearing, locally differentiated to hornblende granite, intrusive sills,
and dykes, metamorphosed, and deformed; metabasalt with pillows (Geoscience
Australia, 2019). Annadale Metadolerite is basic gneisses, which includes
intervening metasedimentary rocks possibly dolerite (Geoscience Australia,
2021).
Rantya Group
Farmcote Gneiss contains metasedimentary rocks and gneiss and is a new unit at
the top of Rantyga Group. It is overlain by the Cues Formation and
Thackaringa Group, and it overlies the Mulculca Formation. The age of the
unit is between 1602 to 1710Ma. Mulculca Formation is abundant
metasedimentary composite gneiss, variable sodic plagioclase-quartz-magnetite
rock, quartz-albite-magnetite gneiss, minor quartz-magnetite rock common,
minor basic gneiss, albite-hornblende-quartz rock (Geoscience Australia,
2019). Ednas Gneiss contains quartz-albite-magnetite gneiss, sodic
plagioclase-quartz-magnetite rock, minor albite-hornblende-quartz rock, minor
quartzo-feldspathic composite gneiss. It is overlain by Mulculca Formation.
Silver City Suite
Formerly mapped in the Thackaringa Group this new grouping accommodates the
metamorphosed and deformed granites. A metagranite containing
quartz-feldspar-biotite gneiss with variable garnet, sillimanite, and
muscovite, even-grained to megacrystic, elongate parallel to enclosing
stratigraphy. It occurs as sills and intrudes both the Thackeringa Group and
the Broken Hill Group. This unit is aged between 1680 to 1707Ma.
Torrowangee Group
Mulcatcha Formation comprises flaggy, quartzose sandstone with lenticular
boulder and arkosic sandstone beds. Yangalla Formation contains boulder
beds, lenticular interbedded siltstone, and sandstone. It overlies the
Mulcatcha Formation (Geoscience Australia, 2020).
Sundown Group
The Sundown Group contains Interbedded pelite, psammopelitic and psammitic
metasedimentary rocks and it overlies the Broken Hill Group. The unit age is
from 1665 to 1692Ma (Figure C-5).
There is also an unnamed amphibolite in Willyama Supergroup, which present
typically medium grained plagioclase and amphibole or pyroxene rich stratiform
or discordant dykes.
Figure C-5: EL 8434 and EL 8435 Solid Geology
Drill hole Information · A summary of all information material to the understanding of the Proposed new drilling has not started yet.
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.
Data aggregation methods · In reporting Exploration Results, weighting averaging techniques, · No metal equivalents have been reported. Rare earth element
maximum and/or minimum grade truncations (e.g., cutting of high grades) and results have been converted to rare earth oxides as per standard industry
cut-off grades are usually Material and should be stated. practice (Castillo Copper 2022f).
· Where aggregate intercepts incorporate short lengths of · No compositing of assay results has taken place, but rather menu
high-grade results and longer lengths of low-grade results, the procedure used options within the Datamine GDB module have been used to create fixed length
for such aggregation should be stated and some typical examples of such 1m assay intervals from the original sampling lengths.
aggregations should be shown in detail.
· The rules follow very similarly to those used by the Leapfrog
· The assumptions used for any reporting of metal equivalent values software in creating fixed length samples.
should be clearly stated.
Relationship between mineralisation widths and intercept lengths · These relationships are particularly important in the reporting · A database of all the historical borehole sampling has been
of Exploration Results. compiled and validated. It is uncertain if there is a strong relationship
between the surface sample anomalies to any subsurface anomalous intersections
· If the geometry of the mineralisation with respect to the drill due to the possible masking by variable Quaternary and Tertiary overburden
hole angle is known, its nature should be reported. that varies in depth from 0-40m.
· If it is not known and only the down hole lengths are reported, · As the strata is tightly folded, the intersected cobalt-rich
there should be a clear statement to this effect (e.g. 'down hole length, true layers are overstated in terms of apparent thickness, however the software
width not known'). calculates a true, vertical thickness.
· Mineralisation is commonly associated with shears, faults,
amphibolites, and a quartz-magnetite rock within the shears, or on or adjacent
to the boundaries of the Himalaya Formation.
· In general, most of the cobalt-rich layers have a north-northwest
to north strike.
Diagrams · Appropriate maps and sections (with scales) and tabulations of · Current surface anomalies are shown on maps released on the ASX
intercepts should be included for any significant discovery being reported (Castillo Copper 2022a and 2022b). All historical surface sampling has had
These should include, but not be limited to a plan view of drill hole collar their coordinates converted to MGA94, Zone 54.
locations and appropriate sectional views.
Balanced reporting · Where comprehensive reporting of all Exploration Results is not · All recent laboratory analytical results have been recently
practicable, representative reporting of both low and high grades and/or reported (see Castillo Copper 2022a, b, c, d, e, and f) for assay results.
widths should be practiced to avoid misleading reporting of Exploration
Results. · Regarding the surface and sampling, no results other than
duplicates, blanks or reference standard assays have been omitted.
Other substantive exploration data · Other exploration data, if meaningful and material, should be · Historical explorers have also conducted airborne and ground
reported including (but not limited to): geological observations; geophysical gravity, magnetic, EM, and IP resistivity surveys over parts of the tenure
survey results; geochemical survey results; bulk samples - size and method of area but this is yet to be fully georeferenced (especially the ground IP
treatment; metallurgical test results; bulk density, groundwater, geotechnical surveys). Squadron Resources conducted an airborne EM survey in 2017 that
and rock characteristics; potential deleterious or contaminating substances. covers Iron Blow and The Sisters, but not the southern prospects.
Further work · The nature and scale of planned further work (e.g., tests for It is recommended that:
lateral extensions or depth extensions or large-scale step-out drilling).
· The non-sampled zones within the Core Library drillholes, BH1,
· Diagrams clearly highlighting the areas of possible extensions, BH2, and DD90-IB3 in the north of the tenure group be relogged and sampled.
including the main geological interpretations and future drilling areas,
provided this information is not commercially sensitive. · A program of field mapping and ground magnetic or EM surveys be
planned and executed.
· CCZ's geology team are in the process of finalising a
comprehensive drilling campaign that will specifically target coring the known
cobalt mineralisation downdip to at least 160m depth. The proposed drilling
program aims to increase the resource confidence is in planning stages. ESF4
applications are close to acceptance (1-2 weeks).
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. END DRLBCGDIBSXDGDGRecent news on Castillo Copper
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