REG - Castillo Copper Ltd - Arya Prospect Drilling Results
17/11/2021 09:35
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RNS Number : 6718S Castillo Copper Limited 17 November 2021
17 November 2021
CASTILLO COPPER LIMITED
("Castillo" or "CCZ" the "Company")
Arya Prospect Drilling Results
Inaugural drilling results show potentially more than 200m of base metal and
graphite mineralisation intersected at Arya Prospect
Castillo Copper Limited (LSE and ASX: CCZ), a base metal explorer primarily
focused on copper across Australia and Zambia, is pleased to announce initial
findings from the drilling campaign currently underway at the Arya Prospect,
located in the Mt Isa region, Queensland.
Highlights
· Three drill-holes have been completed from two drill pads, with
standout, AR_002RC, reaching a depth of 238m:
o Around 200m of dark grey and black carbonaceous siltstone / schist was
intersected, with occurrences of base-metal sulphides and fine-grained
graphite mineralisation, remaining open at depth
· Visible but scattered chalcopyrite (copper sulphide mineralisation)
was observed in drill-hole AR_001RC
· All samples have been dispatched to the laboratory for comprehensive
analysis including base (copper, zinc) / speciality metals (cobalt, REEs) and
total graphitic carbon
· Drilling will continue to the end of November 2021, resuming in 2022,
as there are now new targets to drill-test to determine the full extent of the
underlying systems:
o The next phase of drilling will complete testing the known electromagnetic
anomalies EG01, EG02 & EG10
o The geology team plan to drill test the significant magnetic anomaly to
the south of EG01, EG02 & EG10 as this may be a primary source of base
metal mineralisation
· A comprehensive update will be released once the assays are returned
and the geology team interprets all pertinent fundamentals
Simon Paull, Managing Director of Castillo Copper, commented: "The preliminary
findings from the drilling campaign are quite remarkable, as over 200m of
carbonaceous siltstone and schist, exhibiting occurrences of base metal
sulphides and fine-grained graphite mineralisation, was intersected. This is
an exciting development, particularly given strong prevailing demand for
battery related minerals such as copper, cobalt, and graphite. The Board looks
forward to reviewing the assay results and remains committed to continued
drilling at the Arya Prospect."
MINERALISATION INTERSECTED
Of the three drill-holes completed from two drill-pads at the Arya Prospect,
all intersected thick horizons of black carbonaceous siltstone / schist,
between 30-40m from surface. Circa 200m of dark grey / black carbonaceous
siltstone / schist was intersected in AR_002RC, with coincident base-metal
(portable XRF readings) and graphite mineralisation occurrences recorded
(Appendix A). Scattered, but visible chalcopyrite (copper sulphide
mineralisation) was observed in AR_001RC (Appendix A).
Note, the visible sulphides ranged between 1-3% by volume, but estimations of
graphite content are not possible by portable XRF, and visible estimation was
difficult due to the amount of black schist (estimated 1-5%).
DRILL-HOLE LOCATION
Drill-hole Easting Northing AHD Total Depth Azimuth Dip Type Comments
AR_001RC 351793 7865526 202.2 96 0 -90 RC Quartzite to 42m, dark carbonaceous schist to 90m; Major fault @ 90m
AR_001RCR 351825 7865551 203.4 142 0 -90 RC/PCD Quartzite to 30m then dark carbonaceous siltstones and schists to TD
AR_002RC 352735 7865605 191.8 238 0 -90 RC Quartzite to 29m then dark carbonaceous siltstones and schists to TD
Source: CCZ geology team
All samples have been sent to the laboratory for further analysis, with a
specific request to test for all base / speciality metals, total carbon,
sulphur, and total graphitic carbon.
Drilling campaign
The drilling campaign will run through until the end of November 2021,
resuming in 2022.
Once the assays are returned, the geology team will conduct a full review and
chart the next targets to focus on, so as to fully understand the underlying
systems. The next phase of drilling will complete testing of the known
electromagnetic anomalies: EG01, EG02 and EG10.
In addition, the team intend to drill-test the sizeable magnetic anomaly that
is proximal (south) to EG01, EG02 and EG10 as this potentially could be the
primary source of base metal mineralisation.
SURFACE MAPPING AND ROCKCHIP SAMPLING
The geology team has undertaken a circa 200m-by-200m mapping / rock chip
sampling campaign at the Arya Prospect which is designed to extend the known
surface anomaly to the south. Locations are detailed in Appendix A.
Rock specimens were collected from fourteen locations across the Eldorado
Prospect - further to the south-east. The terrain is rougher, steeper, and
more timbered than the Arya Prospect. The surface geology is more varied, with
signs of copper mineralisation apparent.
Rock specimens collected from the Arya and Eldorado Prospects have been
analysed with the portable XRF gun and magnetic susceptibility tool. The
samples will be forwarded to the laboratory for assaying, but the field
results from both tools suggest the Eldorado Prospect is prospective for
copper mineralisation.
Next steps
In Queensland, the following is set to take place over the coming weeks:
· Assay results and forward drilling plans for the Arya Prospect.
For the lithium projects:
· Ongoing due diligence for the Picasso and Litchfield Lithium
Projects, including return of assay results for surface sampling campaigns.
There are two ongoing steps for the Zambia operations, including:
· Complete the IP survey at the Mkushi Project; and
· Complete work on the inaugural drilling campaign for the Luanshya
Project.
In addition to this release, a PDF version of this report with supplementary
information and images can be found on the Company's website:
https://www.castillocopper.com/asx-announcements/
(https://www.castillocopper.com/asx-announcements/)
For further information, please contact:
Castillo Copper Limited +61 8 6558 0886
Simon Paull (Australia), Managing Director
Gerrard Hall (UK), Director
SI Capital Limited (Financial Adviser and Corporate Broker) +44 (0)1483 413500
Nick Emerson
Luther Pendragon (Financial PR) +44 (0)20 7618 9100
Harry Chathli, Alexis Gore, Elsa Darlington
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.
· 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 Statement
The information in this report that relates to Exploration Results for "Arya
Prospect" 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.
The London Stock Exchange has not reviewed and does not accept
responsibility for the accuracy or adequacy of this release.
APPENDIX A: JORC CODE, 2012 EDITION - TABLE 1 AYRA DRILLING AND SURFACE ROCK
CHIP SAMPLING Section 1 Sampling Techniques and Data
(Criteria in this section apply to all succeeding sections.)
Sampling techniques · Nature and quality of sampling (eg cut channels, random chips, or Drilling
specific specialised industry standard measurement tools appropriate to the
minerals under investigation, such as down hole gamma sondes, or handheld XRF · Samples are taken off a cyclone for every metre drilled, put
instruments, etc). These examples should not be taken as limiting the broad through a three tier, 87.5/12.5 splitter where approximately 2.5 kg of RC chip
meaning of sampling. samples were collected for every metre drilled. The remainder was bagged
separately and stored in case additional sub sampling is required before the
· Include reference to measures taken to ensure sample representivity end of the program.
and the appropriate calibration of any measurement tools or systems used.
· Samples were also composited every four metres where visual
· Aspects of the determination of mineralisation that are Material to inspection did not initially indicate copper mineralisation. All samples
the Public Report. were collected to maximise optimal representation for each sample.
· In cases where 'industry standard' work has been done this would be · Each metre sample had an amount removed for washing and cleaning
relatively simple (eg 'reverse circulation drilling was used to obtain 1 m and sieving then place into metre allocated chip trays (see Figure A1-1).
samples from which 3 kg was pulverised to produce a 30 g charge for fire These chips were logged on site by the rig geologists and those logs have been
assay'). In other cases more explanation may be required, such as where there saved into a spreadsheet and stored on the Company server. Any visible
is coarse gold that has inherent sampling problems. Unusual commodities or mineralisation, alteration or other salient features were recorded in the
mineralisation types (eg submarine nodules) may warrant disclosure of detailed logs. Industry-wide, acceptable, standard practices were adhered to for the
information. drilling and sampling of each metre as per the drilling and sampling
Procedures set out before commencement of the drilling programme.
Rock Chip Sampling
· CCZ completed rock chip sampling methods over at least four (4)
separate surface sampling campaigns and are described in the current ASX
Release, a generalised description of rock chip sample collection is presented
here.
· Rock Chip Samples - were collected up to approximately a 5m
radius around the recorded co-ordinate location. The rock chip fragments that
were collected to make up the sample included a typical fragment size that
approximately ranged from 2-5cm.
· Sub-sampling occurred as described in the section 'Sub-sampling
techniques and sample preparation' in Section 1 of the current Table 1.
· The surface sample results described in this ASX Release are
suitable for the reporting 'exploration results' for mineral prospectivity,
additional exploration work would have to be completed to geologically model
and then estimate a mineral resource.
Drilling techniques · Drill type (eg core, reverse circulation, open-hole hammer, · Arya. Reverse Circulation, RC, and Rotary Air blast (RAB)
rotary air blast, auger, Bangka, sonic, etc) and details (eg core diameter, drilling techniques were utilised for all holes drilled at the Arya Deposit.
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).
Drill sample recovery · Method of recording and assessing core and chip sample recoveries and · For the 2021 program, within acceptable industry standard limits,
results assessed. all samples collected were of near equal mass and recoveries were also within
acceptable limits for RC drilling and all recorded in the daily logs. Every
· Measures taken to maximise sample recovery and ensure representative effort was made on site to maximise recovery including cleaning out the sample
nature of the samples. trays, splitter and cyclone and ensuring that the drillers progressed at a
steady constant rate for the rig to easily complete each metre effectively.
· Whether a relationship exists between sample recovery and grade and
whether sample bias may have occurred due to preferential loss/gain of
fine/coarse material.
Logging · Whether core and chip samples have been geologically and · Every metre drilled and sampled was logged geologically in
geotechnically logged to a level of detail to support appropriate Mineral accordance with industry-wide acceptable standard for RC logging and the
Resource estimation, mining studies and metallurgical studies. logging was qualitative in nature with every metre logged. The 2021 program
recorded visible sulphide, carbonate, and graphite concentrations and
· Whether logging is qualitative or quantitative in nature. Core (or alteration minerals, such as orthoclase, epidote, chlorite, and sericite.
costean, channel, etc) photography.
· The total length and percentage of the relevant intersections logged.
Sub-sampling techniques and sample preparation · If core, whether cut or sawn and whether quarter, half or all core Drilling
taken.
· For the 2021 program, samples with pXRF copper <200ppm will be
· If non-core, whether riffled, tube sampled, rotary split, etc and composited every four metres and all samples were collected to maximise
whether sampled wet or dry. optimal representation for each sample. If XRF is not available, then all
samples with no visible mineralisation will be sampled as above.
· For all sample types, the nature, quality and appropriateness of the
sample preparation technique. · Each metre sample had an amount removed for washing and cleaning
and sieving then place into metre allocated chip trays. These chips were
· Quality control procedures adopted for all sub-sampling stages to logged on site by the rig geologists and those logs have been saved into a
maximise representivity of samples. spreadsheet and stored on the Company server. Any visible mineralisation,
alteration or other salient features were recorded in the logs. Industry wide,
· Measures taken to ensure that the sampling is representative of the acceptable, standard practices were adhered to for the drilling and sampling
in situ material collected, including for instance results for field of each metre as per the Drilling and Sampling Procedures set out before
duplicate/second-half sampling. commencement of the drilling programme.
· Whether sample sizes are appropriate to the grain size of the · Any reporting of significant mineralised intervals was on a
material being sampled. received apparent thickness x interval calculation (i.e., thickness averaged).
Rock Chip Sampling
· All surface samples were collected dry.
· The surface sample results described in this ASX Release are
suitable for the reporting 'exploration results' for mineral prospectivity,
additional exploration work would have to be completed to geologically model
and then estimate a mineral resource.
Quality of assay data and laboratory tests · The nature, quality and appropriateness of the assaying and · CCZ's RC holes will be assayed by an independent laboratory, ALS
laboratory procedures used and whether the technique is considered partial or at Mt Isa, Townsville, or Brisbane Australia. Methods used were as follows:
total.
o Gold - by method Au-AA25 30g charge (fire Assay with AAS finish).
· For geophysical tools, spectrometers, handheld XRF instruments, etc,
the parameters used in determining the analysis including instrument make and o High gold values within oxide zone/supergene zone may need further testing
model, reading times, calibrations factors applied and their derivation, etc. by method Au-SCR21.
· Nature of quality control procedures adopted (eg standards, blanks, o Copper and 32 other - by method ME-MS61 (HF-HN03-HCL04 acid digest, HCL
duplicates, external laboratory checks) and whether acceptable levels of leach and ICP-AES finish).
accuracy (ie lack of bias) and precision have been established.
o Over-limit copper (>10,000 ppm 0.01% ) to be re assayed for copper by
method Cu-OC62 (HF-HN03-HCL04 acid digest, HCL leach and ICP-AES finish).
· These analytical methods are considered as suitable and
appropriate for this type of mineralisation.
For the current drilling program ALS Brisbane will analyse all samples. All
elements except for gold were analysed by method ME-MS61 (41 element testing
via Aqua Regia digest then ICP-AES) and with any copper assays >1%, the
copper will be redone using method Cu-OG46 with ICP-AES. The gold was done by
method AA25. All methods used were both suitable and appropriate for the
styles of mineralisation present in the Big One Deposit at the time of
sampling.
Verification of sampling and assaying · The verification of significant intersections by either independent · All CCZ's RC hole samples have been audited for completeness from
or alternative company personnel. ALS have been reviewed by two independent consultant geologists.
· The use of twinned holes. · For current the rock chip sampling, Independent Laboratory
assaying by ALS has confirmed, within acceptable limits, the occurrences of
· Documentation of primary data, data entry procedures, data high-grade copper inferred from the initial XRF readings. Laboratory
verification, data storage (physical and electronic) protocols. standards and duplicates were used in accordance with standard procedures for
geochemical assaying.
· Discuss any adjustment to assay data.
Location of data points · Accuracy and quality of surveys used to locate drill holes (collar · For rock chip samples positions were recorded by handheld GPS
and down-hole surveys), trenches, mine workings and other locations used in with areas highlighting anomalies sometimes returned to for additional
Mineral Resource estimation. sampling and locations checked by handheld GPS.
· Specification of the grid system used. · .
· Quality and adequacy of topographic control. · Locational data for the 3 drillholes completed. was recorded in
local grid and/or MGA94 zone 54 Easting (mE) and Northing (mN).
· The Arya rock chip sample dataset is anticipated on average to
have up to a +/-20m horizontal level of accuracy in sample locations and range
up to a +/-10m of accuracy in sample locations for vertical accuracy.
Surface sample and assay data had been prepared and compiled into Manifold GIS
System and all data converted to GDA94-Zone 54.
Data spacing and distribution · Data spacing for reporting of Exploration Results. · For the Arya surface sampling modelling for copper, the average
RMS sample-to-sample spacing was as follows:
· Whether the data spacing and distribution is sufficient to establish
the degree of geological and grade continuity appropriate for the Mineral o Rock chip 200m
Resource and Ore Reserve estimation procedure(s) and classifications applied.
· Drillholes are spaced approximately 250m apart.
· Whether sample compositing has been applied.
Orientation of data in relation to geological structure · Whether the orientation of sampling achieves unbiased sampling of · In general, the strike of the Surprise Creek Formation is
possible structures and the extent to which this is known, considering the east-northeast to east, dipping moderately to the north.
deposit type.
· For 'Arya' rock chips there was no fixed orientation as these
· If the relationship between the drilling orientation and the methods were used in the first instance to define distinct areas of
orientation of key mineralised structures is considered to have introduced a anomalisms, based on areas of observed surface mineralisation.
sampling bias, this should be assessed and reported if material.
· For 'Arya' rock chips that produced significant anomalous values
appear to be associated with the mapped fault, fault bounded breccia, and the
Surprise Creek Formation 'PLrd' rock unit ('Prd' historical) that dominates
the 'Arya' prospect to the south of the fault.
· All drilling is intended to be vertical to intersect the dipping
sedimentary beds.
Sample security · The measures taken to ensure sample security. · Each day's RC samples were removed from site and stored in a
secure location off site.
· The RC chip samples taken were securely locked within the vehicle
on site until delivered to Mt Isa for despatch to the laboratory in person by
the field personnel.
Audits or reviews · The results of any audits or reviews of sampling techniques and data. No external reviews or audits have been undertaken, except for the Independent
Geologists Report by SRK in 2019 for the LSE Listing and a review of the
airborne and ground geophysics by the GeoDiscovery Group. Note, the
reference is: Nelson K., Review of open file EM and magnetic geophysical data
at Arya Prospect, GeoDiscovery Group, unpublished confidential report to
Castillo Copper Limited, June 2021, 16pp.
FIGURE A1-1: LOCATION MAP
Available to view on ASX announcement at:
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(https://castillocopper.com/investors/announcements/)
FIGURE A1-2: ARYA COPPER SURFACE SAMPLING GRID
Available to view on ASX announcement at:
https://castillocopper.com/investors/announcements/
(https://castillocopper.com/investors/announcements/)
FIGURE A1-3: ELDORADO COPPER SURFACE SAMPLING GRID
Available to view on ASX announcement at:
https://castillocopper.com/investors/announcements/
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Section 2 Reporting of Exploration Results
(Criteria listed in the preceding section also apply to this section.)
Mineral tenement and land tenure status · Type, reference name/number, location and ownership including · The following mineral tenures are held 100% by subsidiaries of
agreements or material issues with third parties such as joint ventures, Castillo Copper Limited, totalling an area of approximately 961km(2) in the
partnerships, overriding royalties, native title interests, historical sites, "NWQ project":
wilderness or national park and environmental settings.
· EPM 26574 (Valparaisa North) - encompasses the Big One historical
· The security of the tenure held at the time of reporting along with mineral resource, Holder Total Minerals Pty Ltd, granted 12-June-2018 for a
any known impediments to obtaining a licence to operate in the area. 5-year period over 100 sub-blocks (323.3Km2), Expires 11-June-2023.
· EPM 26462 (Big Oxide North) - encompasses the 'Boomerang'
historical mine and the 'Big One' historical mine, Holder: QLD Commodities Pty
Ltd, granted: 29-Aug-2017 for a 5-year period over 67 sub-blocks (216.5Km(2)),
Expires: 28-Aug-2022.
· EPM 26525 (Hill of Grace) - encompasses the Arya significant
aeromagnetic anomaly, Holder: Total Minerals Pty Ltd for a 5-year period over
38 sub-blocks (128.8Km2), Granted: 12-June 2018, Expires: 11-June-2023.
· EPM 26513 (Torpedo Creek/Alpha Project) - Granted 13-Aug 2018 for
a 5-year period over 23 sub-blocks (74.2Km2), Expires 12-Aug-2023; and
· EPM 27440 (The Wall) - An application was lodged on the
12-Dec2019 over 70 sub-blocks (~215Km(2)) by Castillo Copper Limited. The
tenure was granted on the 7(th) March 2021.
Exploration done by other parties · Acknowledgment and appraisal of exploration by other parties. · A selection of historical QDEX / mineral exploration reports has
been reviewed for historical tenures that cover or partially cover the Project
Area in this announcement. Federal and State Government reports supplement the
historical mineral exploration reporting (QDEX open file exploration records).
· Most explorers were searching for Cu-Au-U and/or Pb-Zn-Ag, and,
proving satellite deposit style extensions to the several small sub-economic
copper deposits (e.g., Big Oxide and Josephine).
· With the NWQ Project in regional proximity to Mt Isa and numerous
historical and active mines, the Project area has seen the historical mineral
tenures subject to various styles of surface sampling, with selected locations
typically targeted at specific locations within the NWQ Pillar by shallow
drilling (Total hole depth is typically less than 75m).
· The NWQ project tenure package has a significant opportunity to
be reviewed and explored by modern exploration methods in a coherent package
of EPM's, with three of these forming a contiguous tenure package.
o .
Arya prospect - the five (5) historical exploration reports generated by
various explorers that contributed information and data to this ASX Release
are detailed in the References section of the main body.
Geology · Deposit type, geological setting and style of mineralisation. · The NWQ project is located within the Mt Isa Inlier of western
Queensland, a large, exposed section of Proterozoic (2.5 billion- to
540-million-year-old) crustal rocks. The inlier records a long history of
tectonic evolution, now thought to be like that of the Broken Hill Block in
western New South Wales.
· The NWQ project lies within the Mt Oxide Domain, straddling the
Lawn Hill Platform and Leichhardt River Fault Trough. The geology of the
tenement is principally comprised of rocks of the Surprise Creek and Quilalar
Formations which include feldspathic quartzites, conglomerates, arkosic grits,
shales, siltstones and minor dolomites and limestones.
· The NWQ Pillar project area is cut by a major fault zone,
trending north-northeast to south-southwest across the permits. This fault is
associated with major folding, forming several tight syncline and anticline
structures along its length.
· The desktop studies commissioned by CCZ on the granted mineral
tenures described four main styles of mineralisation account for most mineral
resources within the rocks of the Mt Isa Province (after Withnall &
Cranfield, 2013).
· Sediment hosted silver-lead-zinc - occurs mainly within fine
grained sedimentary rocks of the Isa Super basin within the
· Western Fold Belt. Deposits include Black Star (Mount Isa PbZn),
Century, George Fisher North, George Fisher South (Hilton) and Lady Loretta
deposits.
· Brecciated sediment hosted copper - occurs dominantly within the
Leichhardt, Calvert, and Isa Super basin of the Western Fold Belt, hosted in
brecciated dolomitic, carbonaceous, and pyritic sediments or brecciated rocks
proximal to major fault/shear zones. Includes the Mount Isa copper orebodies
and the Esperanza/Mammoth mineralisation.
· Iron-oxide-copper-gold ("IOCG") - predominantly chalcopyrite,
pyrite magnetite/hematite mineralisation within high grade metamorphic rocks
of the Eastern Fold Belt. Deposits of this style include Ernest Henry,
Osborne, and Selwyn; and
· Broken Hill type silver-lead-zinc - occur within the high-grade
metamorphic rocks of the Eastern Fold Belt. Cannington is the major example,
but several smaller currently sub-economic deposits are known.
· Gold is primarily found associated with copper within the IOCG
deposits of the Eastern Fold Belt. However, a significant exception is noted
at Tick Hill where high grade gold mineralisation was produced, between 1991
and 1995 by Carpentaria Gold Pty Ltd, some 700 000 tonnes of ore was mined at
an average grade of 22.5 g/t Au, producing 15 900 kg Au. The Tick Hill deposit
style is poorly understood (Withnall & Cranfield, 2013).
· ROM Resources had noted in a series of recent reports for CCZ on
the granted tenures, that cover the known mineralisation styles including:
o Stratabound copper mineralisation within ferruginous sandstones and
siltstones of the Surprise Creek Formation.
o Disseminated copper associated with trachyte dykes.
o Copper-rich iron stones (possible IOCG) in E-W fault zones; and
o possible Mississippi Valley Type ("MVT") stockwork sulphide mineralisation
carrying anomalous copper-lead-zinc and silver.
· The Mt Oxide and Mt Gordon occurrences are thought to be breccia
and replacement zones with interconnecting faults. The Mt Gordon/Mammoth
deposit is hosted by brittle quartzites, and Esperanza by carbonaceous shales.
Mineralisation has been related to the Isan Orogeny (1,590 - 1,500 Ma).
· Mineralisation at all deposits is primarily
chalcopyrite-pyrite-chalcocite, typically as massive sulphide within breccias.
· At the Big One prospect, West Australian Metals NL described the
mineralisation as (as sourced from the document "West Australian Metals NL,
1994. Drill Programme at the "Big One" Copper Deposit, North Queensland for
West Australian Metals NL."):
· The targeted lode / mineralised dyke is observable on the
surface. The mineralisation targeted in the 1993 drilling programmed is a
supergene copper mineralisation that includes malachite, azurite, cuprite, and
tenorite, all associated with a NE trending fault (062(o) to 242(o)) that is
intruded by a porphyry dyke.
· The mineralised porphyry dyke is vertical to near vertical
(85(o)), with the 'true width' dimensions reaching up to 7m at surface. o At
least 600m in strike length, with strong Malachite staining observed along the
entire strike length, with historical open pits having targeted approximately
200m of this strike. Exact depth of mining below the original ground surface
is not clear in the historical documents, given the pits are not battered it
is anticipated that excavations have reached 5m to 10m beneath the original
ground surface.
· Associated with the porphyry dyke are zones of fractured and/or
sheared rock, the siltstones are described as brecciated, and sandstones
around the shear as carbonaceous.
· The known mineralisation from the exploration activities to date
had identified shallow supergene mineralisation, with a few drillholes
targeting deeper mineralisation in and around the 200m of strike historical
open A strongly altered hanging wall that contained malachite and cuprite
nodules. Chalcocite mineralization has been identified but it is unclear on
the prevalence of the Chalcocite; and The mineralisation was amenable to high
grade open pit mining methods of the oxide mineralization (as indicated by
numerous historical open pit shallow workings into the shear zone).
· Desktop studies commissioned by CCZ and completed by ROM
Resources and SRK Exploration have determined that the Big One prospect is
prospective for Cuco, and Ag.
· Desktop studies commissioned by CCZ have determined the Boomerang
prospect contains:
· Secondary copper staining over ~800m of strike length.
· Associated with a major east-west trending fault that juxtaposes
the upper Surprise Creek Formation sediments against both the underlying Bigie
Formation and the upper Quilalar Formation units.
· At the 'Flapjack' prospect there is the potential for:
o Skarn mineralisation for Cu-Au and/or Zn-Pb-Cu from replacement
carbonate mineralisation, particularly the Quilalar Formation.
o Thermal Gold Auroele mineralisation is a potential model due to the high
silica alteration in thermal aureole with contact of A-Type Weberra Granite -
related to the Au mineralisation; and/or
o IOCG mineralisation related to chloride-rich fluids.
· At the 'Crescent' prospect there is the potential for:
o Skarn mineralisation for Cu-Au and/or Zn-Pb-Cu from replacement
carbonate mineralisation, particularly the Quilalar Formation; and/or
o Thermal Gold Auroele mineralisation is a potential model due to the high
silica alteration in thermal aureole with contact of A-Type Weberra Granite -
related to the Au mineralisation; and
o IOCG mineralisation related to potassic rich fluids.
· At the 'Arya' prospect there is the potential for:
o Supergene mineralisation forming at the surface along the fault, fault
breccia, and the Surprise Creek Formation 'PLrd' rock unit
o ('Prd' historical).
o Epigenetic replacement mineralisation for Cu (with minor components of
other base metals and gold) from replacement carbonate mineralisation,
particularly the Surprise Creek Formation.
o Skarn mineralisation for Cu-Au and/or Zn-Pb-Cu from replacement carbonate
mineralisation, particularly the Surprised Creek Formation; and/or
o IOCG mineralisation related to chloride rich fluids.
A selection of publicly available QDEX documents / historical exploration
reports have been reviewed, refer to Section 2, sub-section "Further Work" for
both actions in progress and proposed future actions.
Drill hole Information · A summary of all information material to the understanding of the · There is no historical drilling at Arya.
exploration results including a tabulation of the following information for
all Material drill holes: · For the current program, all drillhole information was coded to
the same formatted spreadsheets used by CCZ, being hand-encoded from hard-copy
o easting and northing of the drill hole collar reports, plans, and cross-sections.
o elevation or RL (Reduced Level - elevation above sea level in metres) of the · For CCZ's current drilling program, this information has been
drill hole collar recorded in formatted spreadsheets during the drilling and will be checked and
verified at the conclusion of the current program. The current reported holes
o dip and azimuth of the hole (AR_001RC, AR_001RCR, and AR_002RC) will be fully described in the next ASX
release.
o down hole length and interception depth
· A summary of the holes drilled are given in Table 1 in the main
o hole length. body of text.
· 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 data aggregation methods are utilised in the current ASX
maximum and/or minimum grade truncations (e.g. cutting of high grades) and Release, since the sampling types are surface rock chip samples.
cut-off grades are usually Material and should be stated.
· Where aggregate intercepts incorporate short lengths of high-grade
results and longer lengths of low-grade results, the procedure used for such
aggregation should be stated and some typical examples of such aggregations
should be shown in detail.
· The assumptions used for any reporting of metal equivalent values
should be clearly stated.
Relationship between mineralisation widths and intercept lengths · These relationships are particularly important in the reporting of · The strike of the country rock is northeast to east, with the
Exploration Results. deep Arya conductor is orientated east - west. The smaller, shallower
conductors strike north-northeast to northeast. The main faulting trends is
· If the geometry of the mineralisation with respect to the drill hole northeast.
angle is known, its nature should be reported.
· When available, all mineralised intervals (i.e., >500ppm) will
· If it is not known and only the down hole lengths are reported, there be reported in future ASX releases as the "as-intersected" apparent thickness
should be a clear statement to this effect (eg 'down hole length, true width (in metres) and given that all drillholes dip at -90 degrees from the
not known'). horizontal, true intersection widths will be calculated during the block
modelling process.
Diagrams · Appropriate maps and sections (with scales) and tabulations of · This part will be done once CCZ's current drilling program is
intercepts should be included for any significant discovery being reported completed, and all samples have been assayed and verified.
These should include, but not be limited to a plan view of drill hole collar
locations and appropriate sectional views. · Appropriate diagrams are presented in the body and the Appendices
of the current ASX Release. Where scales are absent from the diagram, grids
have been included and clearly labelled to act as a scale for distance.
· Maps and Plans presented in the current ASX Release are in MGA94
Zone 54, Eastings (mN), and Northing (mN), unless clearly labelled otherwise.
Balanced reporting · Where comprehensive reporting of all Exploration Results is not · Comprehensive reporting is planned once CCZ's current drilling
practicable, representative reporting of both low and high grades and/or program has all sample queries returned and have been verified.
widths should be practiced to avoid misleading reporting of Exploration
Results. o Appropriate diagrams are presented in the body and the Appendices of the
current ASX Release. Where scales are absent from the diagram, grids have
been included and clearly labelled to act as a scale for distance.
· A complete comparison of visual mineralisation estimated by the
site geologist will be published once all assays are returned. All
intersected intervals are apparent thicknesses in metres.
Other substantive exploration data · Other exploration data, if meaningful and material, should be GEOTEM & PROTEM:
reported including (but not limited to): geological observations; geophysical
survey results; geochemical survey results; bulk samples - size and method of · The airborne electromagnetic GEOTEM geophysical survey undertaken
treatment; metallurgical test results; bulk density, groundwater, geotechnical by BHP Minerals in 1997 on historical tenure EPM11383 & EPM1152. A total
and rock characteristics; potential deleterious or contaminating substances. of 726-line kilometres were flown on a SE-NW, flown by 'Geoterrex-Dighem Pty
Limited' at a mean height of approximately 105m above the ground surface (line
spacing 500m apart). Previous interpretations the penetration of the GEOTEM
method to have an estimated range of between 200-300m below the ground
surface, this is dependent on conductivity contrasts, size, and attitude of
the subsurface targets. Eleven (11) anomalies were identified, with four (4)
recommended for follow up, with three (3) of the four (4) anomalies followed
up by ground geophysical at what CCZ calls the 'Arya' prospect. The BHP
Minerals 1997 GEOTEM survey information was extracted from QDEX Data to
accompany the QDEX report information.
· The 'Arya' prospect anomalies are EG01, EG02, EG10, with the
geophysical observations of the body and Appendices of the current ASX
Release, including the PROTEM observations. The PROTEM observations are
anticipated to have a deeper penetration than the GEOTEM observations, based
on the PROTEM loop, survey traverse, and/or depth sounding method applied.
QUESTEM & GENIE-EM:
· The airborne electromagnetic GEOTEM geophysical survey undertaken
by Mount Isa Mines in 1991 on historical tenure EPM7448, EPM7338, and EPM7863.
A total of approximately 600km-line kilometres (exact line length would need
to be extracted from digitised images) would were flown on a SE-NW, flown by
'Aerodata Holdings Limited' at a mean height of approximately 120m above the
ground surface (line spacing 400m apart). In a previous ASX release (July
2020) Xplore Resources Pty Ltd interprets the penetration of the QUESTEM
method to have an estimated range of between 200-300m below the ground
surface, this is dependent on conductivity contrasts, size, and attitude of
the subsurface targets. Twentynine (29) anomalies were identified across the
three (3) historical tenure, with six (6) recommended for follow up ground
geophysical survey for historical tenure EPM7448, and one of these L4 near the
Arya prospect.
· Arya prospect anomaly L4 followed up by a ground electromagnetic
traverse by Mount Isa Mines GENIE-EM is to the west of the EG02 BHP minerals
anomaly.
· Queensland Government Data: 'PLrd' rock unit lower boundary from
the Surprise Creek Formation sourced from QSpatial and aligns with GeoResGlobe
- this is equivalent to the historical tenure reports 'Prd' rock unit lower
boundary from the Surprise Creek Formation.
GEODISCOVERY REVIEW
The study of Nelson (2021) concluded that:
· Whilst hard copies of the 1997 BHP ground EM data are available,
no digital data is on open file. Hard copy profiles have been visually
interpreted, however due to lack of digital data it cannot be remodelled.
The historic BHP model results and survey locations have not been provided and
there is uncertainty in the location of Anomaly E02.
· Magnetic modelling, CDI and LEI of the TEMPEST survey line
indicate the BHP depth estimate of conductive from the EG01 sounding is likely
over estimated. Depth to main conductive sources appears to be between
around 200m beneath surface (Nelson (2021).
· EG02 appears to be associated with a fault and EG10 appears to be
more surficial.
· It is recommended that the LEI of the TEMPEST survey (most recent
AEM data acquired in the region), along with magnetic model output be used to
plan the next drill campaign (Figure 10 - 12). The current drill plan could
be improved to better test the modelled conductive sources and structural
features.
· If the drill testing of the conductive sources indicates the
presence of prospective lithologies and/or mineralisation, then consideration
should be given to acquiring detailed ground EM and magnetic coverage to
further assist targeting.
Figures A2-1 to A2-4 illustrate the above conclusions.
Further work · The nature and scale of planned further work (eg tests for lateral · Further work will consist of a combination of:
extensions or depth extensions or large-scale step-out drilling).
o Fourteen (14) hole RC drilling Program
· Diagrams clearly highlighting the areas of possible extensions,
including the main geological interpretations and future drilling areas, o Soil and or Rock chip sampling
provided this information is not commercially sensitive.
o Ground IP or EM Survey
FIGURE A2-1: DRILL-HOLE LOCATION
AR_001RC 351793 7865526 202.2 96 0 -90 RC Quartzite to 42m, dark carbonaceous schist to 90m; Major fault @ 90m.
AR_001RCR 351825 7865551 203.4 142 0 -90 RC/PCD Quartzite to 30m then dark carbonaceous siltstones and schists to TD
AR_002RC 352735 7865605 191.8 238 0 -90 RC Quartzite to 29m then dark carbonaceous siltstones and schists to TD
Source: CCZ geology team
FIGURE A2-2: DRILL-HOLE LOCATION VS EM MODELLED BODIES
Available to view on ASX announcement at:
https://castillocopper.com/investors/announcements/
(https://castillocopper.com/investors/announcements/)
FIGURE A2-3: AR_001RCR CHIP TRAY 111-120M
Available to view on ASX announcement at:
https://castillocopper.com/investors/announcements/
(https://castillocopper.com/investors/announcements/)
FIGURE A2-4: ARYA DRILLHOLE AR_002RC CHIP TRAY 41-50M
Available to view on ASX announcement at:
https://castillocopper.com/investors/announcements/
(https://castillocopper.com/investors/announcements/)
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