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RNS Number : 5583C Castillo Copper Limited 12 October 2022
12 October 2022
CASTILLO COPPER LIMITED
("Castillo" or the "Company")
Drilling hits targeted cobalt zones & wide pegmatite intercepts at Broken
Hill
Castillo Copper Limited (LSE and ASX: CCZ), a base metal explorer primarily
focused on copper across Australia and Zambia, is pleased to announce that
four drill-holes for a total of 488m have been completed at the Tors Tank
Prospect (Appendix B), within the BHA Project's East Zone (Appendix A), with
encouraging initial observations and interpretations. Subject to confirmation
from final assay results, the geology team believe there is potential for
cobalt and REE mineralisation.
HIGHLIGHTS
· Four drill-holes for 488m were completed at the Tors Tank Prospect,
within the BHA Project's East Zone (Appendix A), which delivered encouraging
initial observations:
o All four drill-holes hit targeted cobalt mineralisation zones, evidenced
by intersecting sequences comprising clay, amphibolite, schist, and gneiss
o Qualitative logging identified multiple disseminated sulphide layers
(mostly pyrite), up to 12m thick, associated with amphibolite layers that can
potentially host cobalt mineralisation
o Field XRF observations, which are subject to final assay results,
indicated the presence of cobalt mineralisation within these amphibolite zones
o The intersected geology is interpreted to be consistent with observations
by previous explorers, including Broken Hill North(1), across the 1970-80s
· Proximal to the amphibolite layers, there are significant
magnetite-rich zones - associated with pegmatite up to 14m thick - that
potentially hosts rare earth elements (REEs):
o This interpretation is based on recently re-assayed diamond core from
drill-hole DD90_IB3 at the Iron Blow Prospect which returned up to 1,270ppm
TREO(2)
· The Board is delighted with the start to the drilling campaign,
particularly the positive interpretations on the Tors Tank Prospect, and looks
forward to receiving the final assay results within the coming weeks
Dr Dennis Jensen, Managing Director of Castillo Copper, commented: "The
drilling campaign has got off to an excellent start, with initial
interpretations from the geology team confirming that targeted cobalt zones
have been intersected. Moreover, whilst subject to final assay results, the
Board is delighted to learn that significant pegmatite zones have been
intersected which could potentially host rare earth elements."
Drilling completed at Tors Tank Prospect
As noted in Figure 1, the drilling intersected a geological sequence
comprising clay, amphibolite, schist, gneiss, and pegmatite that appears to be
dipping moderately. More significantly, the intersected geology is interpreted
to be consistent with observations by previous explorers, including Broken
Hill North(1), during the 1970-80s.
FIGURE 1: QUALITATIVE LOGGING MINERALS PRESENT DRILL-HOLES TT_001RC-004RC
Borehole From (m) To (m) Apparent Thick. (m) Magnetite Epidote (%) Chlorite (%) Sulphides (%) Comments
(%)
TT_001RC 1 21 20 1-5 0 1-3 1-3 Amphibolite, sulphides (mostly pyrite) & trace chalcopyrite
TT_001RC 25 38 13 1-12 0 0 0 Pegmatite & clay
TT_001RC 66 75 9 0 0-2 1-3 1-3 Schist & sulphides (pyrite)
TT_001RC 110 118 8 1-3 0 1-3 0-1 Schist, Iron oxide & haematite (1-3%)
TT_002RC 4 13 9 2-40 0 0 0-2 Clayey amphibolite & haematite (2-15%)
TT_002RC 26 30 4 1-5 0 0 0 Clay & schist
TT_002RC 44 47 3 1-5 0 0-1 0-1 Pegmatite
TT_002RC 79 80 1 0 0 1-2 1-3 Pyrite band
TT_003RC 8 30 22 3-40 1-2 1-3 1-4 Clay & amphibolite
TT_003RC 72 79 7 1-10 0 1-2 0-1 In schist
TT_003RC 106 132 26 0 1-3 1-3 1-5 Mostly schist & gneiss
TT_004RC 1 6 5 1-5 0 0 0 Amphibolite
TT_004RC 21 44 23 1-30 0 0 0 Amphibolite & schist
TT_004RC 97 104 7 1-5 0 0 0 Schist
TT_004RC 108 114 6 0 1-3 0-1 1-4 Schist & sulphides (mostly pyrite)
Note: Ranges of minerals represent qualitative estimation during geological
modelling.
Source: CCZ geology team
Cobalt mineralisation
During the qualitative logging process, multiple disseminated sulphide layers
(mostly pyrite) up to 12m thick were identified. This is significant, as
previous work by North Broken Hill(1) suggested the pyrite hosts cobalt
mineralisation. Further analysis of the samples showed that pyrite is mostly
associated with amphibolite layers and, thinner, sparser horizons which also
occur and are spread within interbedded schist and gneiss layers.
Supporting the interpretation that cobalt mineralisation is apparent, but
subject to final assay confirmation, field XRF observations indicated positive
readings within the amphibolite zones.
REE potential
Proximal to the amphibolite layers are significant magnetite zones which are
directly associated with pegmatite up to 14m thick (Figure 1) that, subject to
final assay confirmation, could potentially host REEs.
This interpretation is based on recent re-assays of diamond core from
drill-hole DD90_IB3 at the Iron Blow Prospect. It has comparable geology and
confirms the presence of high-grade REEs within the BHA Project's East Zone.
Notably, the best intersection was 8m @ 1,270ppm TREO(2).
RC samples
With the conclusion of the drilling campaign at the Tors Tank Prospect, all
488 one metre RC samples collected were geologically logged (Figure 2) then
dispatched to ALS' Adelaide laboratory for processing and analysis.
FIGURE 2: LOGGING CHIPS AT TT_003RC
Location: 6460000mN, 570000mE
Source: CCZ geology team
PHOTO GALLERY 1: DRILLING AT TT_001RC & TT_004RC SITE
Location: 6460000mN, 570000mE
Source: CCZ geology team
PHOTO GALLERY 2: MICROGRAPH OF PYRITE AT 111M IN TT_003RC
Source: CCZ geology team
Photo Gallery 2 shows a photo-microscope at 40x magnification of a gneiss
containing disseminated pyrite from TT_003RC. Across the Broken Hill region,
this type of mineralisation has been shown to contain cobalt in solid
solution(3).
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 4582 3500
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) Leyh:
a. Leyh, W.R., 1976, Progress Report on Exploration Licence, No.
846 Iron Blow -Yellowstone Area, Broken Hill, New South Wales for the six
months period ended 29th June 1976, North Broken Hill Limited, Report
GS1976-198, Jul 76, 88pp
b. Leyh, W.R., 1977a, Progress Report on Exploration Licence,
No. 846 Iron Blow -Yellowstone Area, Broken Hill, New South Wales for the six
months period ended 29th December 1976, North Broken Hill Limited, Report
GS1976-198, Feb 1977, 24pp
c. Leyh W.R., 1977b, Progress Report on Farmcote Exploration
Licenses 780 and 782, Farmcote Area, Broken Hill, NSW for the three months to
5th March 1977, North Broken Hill Limited for the NSW Geological Survey,
(GS1977-078)
d. Leyh W.R., 1977c, Progress Report on Farmcote Exploration
Licenses 780 and 782, Farmcote Area, Broken Hill, NSW for the three months to
23rd May 1977, North Broken Hill Limited for the NSW Geological Survey,
(GS1977-078)
e. Leyh W.R., 1978, Progress Report on Farmcote Exploration
Licenses 780 and 782, Farmcote Area, Broken Hill, NSW for the three months to
27 October 1978, North Broken Hill Limited for the NSW Geological Survey,
(GS1977-078)
f. Leyh W.R., 1978 Progress Report on Exploration Licenses
1099 and 1100 for the six months to 27 October 1978, North Broken Hill Limited
for the NSW Geological Survey, (GS1978-407)
g. Leyh, W.R., 1990, Exploration Report for the Third Six
Monthly Period ended 12th June 1990 for EL 3238 (K Tank), Broken Hill
District, New South Wales for the six months period, Pasminco Limited, Report
GS1989-226, Jun 90, 22pp
h. Leyh, W.R., and Lees T.C., 1977, Progress Report on
Exploration Licence, No. 846 Iron Blow -Yellowstone Area, Broken Hill, New
South Wales for the six months period ended 29th June 1977, North Broken Hill
Limited, Report GS1976-198, Jul 77, 35pp
i. Leyh, W.R., and Larson P.D., 1981, Final Report for the
Third Six Monthly Period ended 12th June 1990 for EL 3238 (K Tank), Broken
Hill District, New South Wales for the six months period, Pasminco Limited,
Report GS1989-226, Jun 90, 22pp
2) CCZ ASX Release - 5 May 2022
3) COB ASX Release - 19 September 2022 (Annual Report 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: DRILL-HOLES AT TORS TANK PROSPECT
FIGURE B1: TORS TANK RC DRILLING STATISTICS
SiteID HoleID Est. Easting (GDA94) Est. Northing (GDA94) TDepth (m) Azimuth Planned Planned DipH Hole Type Source Start End
2022_TT_01 TT_004RC 571250 6451480 120 180 -60 RC CCZ 03-Oct-22 04-Oct-22
2022_TT_02 TT_001RC 571370 6451395 120 180 -60 RC CCZ 30-Sep-22 01-Oct-22
2022_TT_03 TT_003RC 571425 6451280 140 180 -60 RC CCZ 02-Oct-22 03-Oct-22
2022_TT_04 TT_002RC 571475 6451250 108 180 -60 RC CCZ 01-Oct-22 02-Oct-22
488
Source: CCZ geology team
FIGURE B2: DRILL-HOLE LOCATIONS AT TORS TANK PROSPECT
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 · Diamond drilling of NQ or BQ diameter is planned later in the
instruments, etc.). These examples should not be taken as limiting the broad current program. The location is yet to be decided but will be located next
meaning of sampling. to an RC hole already drilled.
· Include reference to measures taken to ensure sample Reverse Circulation ('RC') Drilling
representivity and the appropriate calibration of any measurement tools or
systems used. · RC drilling at Tors Tank was used to obtain a representative
sample by means of riffle splitting with samples submitted for analysis using
· Aspects of the determination of mineralisation that are Material the above-mentioned methodologies.
to the Public Report.
· Four (4) holes for a total of 488m have been completed to the
· In cases where 'industry standard' work has been done this would 4(th) October 2022, all at the Tores Tank Prospect.
be relatively simple (e.g., 'reverse circulation drilling was used to obtain 1
m samples from which 3 kg was pulverised to produce a 30g charge for fire · The RC drilling technique was used to obtain a representative
assay'). In other cases, more explanation may be required, such as where there sample by means of a cone or riffle splitter with samples submitted for assay
is coarse gold that has inherent sampling problems. Unusual commodities or by mixed acid digestion and analysis via ICP-MS + ICP-AES with anticipated
mineralisation types (eg submarine nodules) may warrant disclosure of detailed reporting a suite of 48 elements (sulphur >10% by LECO).
information.
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. One cored hole of NQ or BQ
triple or standard tube, depth of diamond tails, face-sampling bit or other diameter will be completed after all the RC holes have been completed.
type, whether core is oriented and if so, by what method, etc.).
· Diamond drilling will be completed with standard diameter,
conventional HQ and NQ with historical holes typically utilizing RC and
percussion pre-collars to an average 30 metres (see Drillhole Information for
further details).
Drill sample recovery · Method of recording and assessing core and chip sample recoveries · Reverse Circulation ('RC') Drilling - Reverse circulation sample
and results assessed. recoveries were visually estimated during drilling programs. Where the
estimated sample recovery was below 100% this was 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 employed 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. · Historical cored drillholes were well documented and generally
have >90% core recovery.
· No relationship between sample recovery and grade has been
observed.
· No relationship between sample recovery and grade has been
observed.
Logging · Whether core and chip samples have been geologically and · The drilling that did occur was completed to modern-day
geotechnically logged to a level of detail to support appropriate Mineral standards. The preferred exploration strategy in the eighties and early
Resource estimation, mining studies and metallurgical studies. 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. In this program holes are planned to
(or costean, channel, etc) photography. varying depths ranging from 100-160m.
· The total length and percentage of the relevant intersections · No downhole geophysical logging took place; however, measurements
logged. of magnetic susceptibility were taken at the same 1m intervals as the PXRF
readings were taken.
Sub-sampling techniques and sample preparation · If core, whether cut or sawn and whether quarter, half or all · Core samples will be hand-split or sawn with re-logging of
core taken. available historical core indicating a 70:30 (retained: assayed) split was
typical. The variation of sample ratios noted are considered consistent with
· If non-core, whether riffled, tube sampled, rotary split, etc and the sub-sampling technique (hand-splitting).
whether sampled wet or dry.
· No second half samples were submitted for analysis, but
· For all sample types, the nature, quality, and appropriateness of duplicates have been taken at a frequency of 1:20 samples collected.
the sample preparation technique.
· It is considered water planned to be used for core cutting is
· Quality control procedures adopted for all sub-sampling stages to unprocessed and unlikely to have introduced sample contamination.
maximise representivity of samples.
· Procedures relating to the definition of the line of cutting or
· Measures taken to ensure that the sampling is representative of splitting are not available. It is expected that 'standard industry
the in-situ material collected, including for instance results for field practice' for the period was applied to maximize sample representivity.
duplicate/second-half sampling.
· Quarter core will be submitted to ALS for chemical analysis using
· Whether sample sizes are appropriate to the grain size of the industry standard sample preparation and analytical techniques.
material being sampled.
· The sample interval details and grades quoted for cored intervals
described in various maps in the main section are given in previous ASX
releases (Castillo Copper 2022a, b, c, d, e, f).
Quality of assay data and laboratory tests · The nature, quality and appropriateness of the assaying and · The nature and quality of all proposed assaying and laboratory
laboratory procedures used and whether the technique is considered partial or procedures 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 will processed at independent commercial laboratories
including Australian Laboratory Services, (ALS) at Adelaide, Brisbane, and
Perth (for any core metallurgical beneficiation).
· Laboratory inserted standards, blanks and duplicates were
analysed per industry standard practice. The first batch of analyses is
awaited to determine any evidence of bias from these results.
· None of the drillholes have been twinned yet until the location
of the planned cored hole is chosen.
· To monitor the accuracy of assay results from drilling, CRM
standards were included in the assay sample stream at an average rate of 1:30.
Internal lab standards will be routinely included by ALS Brisbane for the CCZ
retesting.
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 of an Access
verification, data storage (physical and electronic) protocols. Database but will be loaded to a Datamine GDB database through the independent
management of ROM Resources. The database procedures strictly apply
· Discuss any adjustment to assay data. integrity rules to all downhole and measurement recordings. If 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.
· Samples returning assays below detection limits are assigned half
detection limit values in the database.
· All significant intersections are verified by ROM Resources'
Exploration Manager and an alternative Company representative.
Location of data points · Accuracy and quality of surveys used to locate drill holes · In general, locational accuracy does vary, depending upon whether
(collar and down-hole surveys), trenches, mine workings and other locations the historical surface and drillhole samples were digitised off plans or had
used in Mineral Resource estimation. their coordinated tabulated. Many samples were originally reported to AGD66
or AMG84 and have been converted to MGA94 (Zone 54)
· Specification of the grid system used.
· The holes are currently surveyed with handheld GPS, awaiting more
· Quality and adequacy of topographic control. accurate DGPS survey. It is thus estimated that locational accuracy
therefore varies between 2-4m until the more accurate surveying is completed.
· The quality of topographic control (GSNSW 1 sec DEM) is deemed
adequate for the purposes of the exploration drilling program.
Data spacing and distribution · Data spacing for reporting of Exploration Results. · The average sample spacing from the current drilling program
across the tenure varies per prospect, and sample type, as listed in Table
· Whether the data spacing and distribution is sufficient to C1-1, below:
establish the degree of geological and grade continuity appropriate for the
Mineral Resource and Ore Reserve estimation procedure(s) and classifications Table C-2: EL 8434 Drillhole Spacing
applied.
Prospect Drillholes in Model RMS Drillhole Spacing (m)
The Sisters
· Whether sample compositing has been applied. Iron Blow
Tors Tank 4 127
Fence Gossan
Ziggy's Hill
Reefs Tank
· 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 · Historical drill holes at the BHAE are typically drilled
possible structures and the extent to which this is known, considering the vertically for auger and RAB types (drilled along section lines) and angled at
deposit type. -55˚ or -60˚ to the horizontal and drilled perpendicular to the mineralised
trend for RC and DDH (Figure C-1).
· If the relationship between the drilling orientation and the
orientation of key mineralised structures is considered to have introduced a · Drilling orientations are adjusted along strike to accommodate
sampling bias, this should be assessed and reported if material. folded geological sequences. All Tors Tank holes were designed to drill
toward grid south at an inclination of 60 degrees from horizontal.
· 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. · Sample security procedures are considered 'industry standard' for
the current period.
· Samples obtained during drilling completed between 30/9/22 to the
4/10/22 were transported by exploration employees or an independent courier
directly from Broken Hill to ALS Laboratory, Adelaide.
· The Company considers that risks associated with sample security
are limited given the nature of the targeted mineralisation.
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 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.
· Historical drill holes at the BHAE are typically drilled
vertically for auger and RAB types (drilled along section lines) and angled at
-55˚ or -60˚ to the horizontal and drilled perpendicular to the mineralised
trend for RC and DDH (Figure C-1).
· Drilling orientations are adjusted along strike to accommodate
folded geological sequences. All Tors Tank holes were designed to drill
toward grid south at an inclination of 60 degrees from horizontal.
· 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.
· Sample security procedures are considered 'industry standard' for
the current period.
· Samples obtained during drilling completed between 30/9/22 to the
4/10/22 were transported by exploration employees or an independent courier
directly from Broken Hill to ALS Laboratory, Adelaide.
· The Company considers that risks associated with sample security
are limited given the nature of the targeted mineralisation.
Audits or reviews
· The results of any audits or reviews of sampling techniques and
data.
· No external audits or reviews have yet been undertaken.
FIGURE C1-1: TORS TANK DRILLHOLE LOCATION OCTOBER 2022
Notes:
1. Historical drillholes shown and deposit block model mask, All
holes orientated south at -60 degrees from horizontal.
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 Header information about all drillholes completed at Tors Tank have been
exploration results including a tabulation of the following information for tabulated in the main body text.
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, DD90-IB3 is a good candidate or hyperspectral logging.
provided this information is not commercially sensitive.
· A program of field mapping and ground magnetic or EM surveys be
planned and executed.
· Complete the comprehensive drilling campaign that will comprise
RC drilling and specifically target coring the known cobalt mineralisation
downdip to at least 100m depth at one of the prospects. The current drilling
program is also designed to increase the resource confidence and now has its
ESF4 applications approved by the NSW Resource Regulator.
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