REG - Castillo Copper Ltd - Visible copper intercepts continue at Big One

Castillo CopperAnnouncement

14/12/2020 07:00

RNS Number : 4653I
  
Castillo Copper Limited
  
14 December 2020
  
 

 
14 December 2020
CASTILLO COPPER LIMITED

("Castillo" or the "Company")
 
Shallow, visible copper oxide and sulphide intercepts up to 12m continue at Big One Deposit
 
Castillo Copper Limited (LSE and ASX: CCZ), a base metal explorer primarily focused on copper across Australia and Zambia, is pleased to announce incremental shallow, visible copper oxide (malachite) and sulphide (chalcocite) mineralisation was recorded in six drill-holes, with cumulative intercepts up to 12m at the Big One Deposit within the core Mt Oxide Project in Queensland, Australia.
 
Highlights  
·    A further six drill-holes completed at the Big One Deposit all intersected visible, shallow copper oxides and sulphides up to 12m indicating potential extensions to known mineralisation at depth providing a compelling case for scalability, including:  
o  BO_301RC: 12m cumulative - 3m from 28-31m & 9m from 32-41m - Black copper oxides and malachite (oxide)
o  BO_303RC: 10m cumulative - 3m from 25-28m & 7m from 28-35m- Black copper oxides, malachite (oxide), and chalcocite (sulphide)
o  BO_306RC: 7m cumulative - 4m from 93-97m and 3m from 99-102m- Malachite, pyrite, and chalcocite
o  BO_305RC: 5m cumulative - 4m from 30-34m & 1m from 39-40m- Malachite and chalcocite
o  BO_302RC: 3m from 36-39m - Black copper oxides 
o  BO_304RC: 1m from 81-82m - Azurite and malachite
·    Castillo's geology team undertook a thorough review of the sample trays and interpreted the following: 
o  Two-to-three zones of copper mineralisation are apparent within BO_301RC-306RC
o  Malachite and chalcocite, apparent within BO_301RC, is within the supergene / transitional zone below the oxide layer and relatively close to historic workings 
o  With chalcocite, pyrite and haematite observed, BO_303RC / BO_304RC are likely in the transitional zone  
o  Identifying haematite and quartz alteration is significant, as large Mt Isa Block deposits are known to have haematisation and silicification linked with copper mineralisation
·    Assays results, which were fast-tracked, should be received shortly, while the Big One Deposit still delivers significant exploration upside with a further 22 drill-holes to complete
·    A clearer picture of the Big One Deposit continues to emerge as the campaign evolves, with a shallow high-grade system apparent comprising grades up to 28.4% Cu
·    As Big One Deposit was previously a mining lease (ML5481), with ~4,400t of supergene ore mined in 1997 yielding ~3.5% Cu, Castillo's Board's current strategic intent comprises:
o  Leveraging historic and current drilling results, model up a JORC compliant resource then apply for a new mining lease 
Next steps 
·    Provide an update on the next batch of assay results, further drilling logs and complete the Big One Deposit campaign, then move on to Arya Prospect
 
Simon Paull, Managing Director of Castillo Copper, commented: "Confirming shallow, visible copper oxides and sulphides across six drill-holes to intercept widths up to 12m is an outstanding result. Encouragingly, it continues to build a compelling case for the scalability of the Big One Deposit and potential for known mineralisation to be extended at depth. Once the current campaign is complete, the Board's strategic goal is to model up a JORC compliant resource for the Big One Deposit then commence applying for a mining lease."    
Ged Hall, UK Director of Castillo Copper, said: "We continue to build a compelling case for the Big One Deposit, as wide shallow intercepts with visible copper mineralisation is precisely the desired outcome. There are still a further 22 drill-holes to complete in the current campaign, which delivers significantly further potential exploration upside ahead."   
Notably, these results complement preliminary assay results for visually logged mineralised intersections in four of seven drill-holes completed (Figure1; BO_201-213RC) in the first tranche. The full assay results for the seven drill-holes are currently being finalised at the laboratory and are expected to be returned shortly.  Figure 1 contains a comparison to these analyses of the visually logged mineralised zones in the next six drill-holes just completed (BO_301RC to 306RC).
Collectively, the fresh observations highlight the potential for extensions to known mineralisation at depth and underpin a more compelling case for scalability at the Big One Deposit.  



FIGURE 1: BIG ONE DEPOSIT OBSERVED MINERALISATION FOR BO_301RC-306RC 




BO_301RC: 12m cumulative - 3 from 28-31m and 9 from 32-41m- Black copper oxides and malachite




BO_303RC: 10m cumulative - 3m from 25-28m and 7m from 28-35m - Black copper oxides, malachite, and chalcocite




BO_306RC: 7m cumulative - 4m from 93-97m and 3m from 99-102m- Malachite, pyrite, and chalcocite




BO_305RC: 5m cumulative - 4m from 30-34m and 1m from 39-40m- Malachite and chalcocite




BO_302RC: 3m from 36-39m - Black copper oxides




BO_304RC: 1m from 81-82m - Azurite and malachite




INITIAL ASSAY RESULTS FROM Q4 2020 DRILLING CAMPAIGN




BO_213RC: 7m @ 1.37% Cu from 57m incl: to 3m @ 2.18% Cu from 58m 




BO_211RC: 1m @ 4.14% Cu from 65m 




BO_206RC: 7m @ 0.54% Cu from 55m incl: 2m @ 1.35% Cu from 60m




BO_207RC: 4m @ 0.43% Cu from 85m incl: 2m @ 1.03% Cu from 85m



 
Strategic intent: apply for a new mining lease 
 
Previously, Big One Deposit was a mining lease and in 1997 circa 4,400t of ore was mined from the supergene zone, with an average reported grade of ~3.5% Cu.  While the output was sold to a nearby heap leach operation at Mt Cuthbert, mining operations are believed to have been suspended due to the downturn in base metal prices arising from the Asian financial crises. 
 
Further, the syndicate that oversaw production in 1997 used ripping to target the near vertical orebody, then loaded mined product onto haulage trucks for direct transport to the buyer's facility.  Interestingly, the mining was shallow and expanded upon three remnant pits worked on in 1993 - East (Pit 1), Central (Pit 2) & West (Pit 3) - which reached up to circa 34m along strike and 5-10m.
The Board's strategic intent for the Big One Deposit is to leverage historic and current drilling results to model up a JORC compliant resource then apply for a new mining lease. 
 
In addition to this release, a PDF version of this report with supplementary information can be found on the Company's website: https://www.castillocopper.com/asx-announcements/
 
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:
o  The Mt Oxide project 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.
o  Four high-quality prospective assets across Zambia's copper-belt which is the second largest copper producer in Africa.
o  A large tenure footprint proximal to Broken Hill's world-class deposit that is prospective for zinc-silver-lead-copper-gold.
o  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 the "Big One Deposit" relates to Exploration Results is based on information compiled or reviewed by Mr Mark Biggs, a consultant 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.
 




 
APPENDIX A: DRILL COLLAR DETAILS & OBSERVATIONS 
Tables B1 and B2 below list the new drill-holes completed, and the summary of visible mineralisation.
 
TABLE B1: TRANCHE 2 COLLAR LOCATIONS
 



Hole_ID


Orig_East


Orig_North


Orig_RL


Max_Depth


END_DATE


START_DATE


Type


Orig_Grid_ID




BO_2020_301RC


335407.5


7880328.2






53.0


02-Nov-20


05-Dec-20


RC


MGA94_54




BO_2020_302RC


335382.6


7880317.6






59.0


05-Dec-20


05-Dec-20


RC


MGA94_54




BO_2020_303RC


335429.0


7880338.0






53.0


06-Dec-20


06-Dec-20


RC


MGA94_54




BO_2020_304RC


335447.9


7880312.5






107.0


06-Dec-20


06-Dec-20


RC


MGA94_54




BO_2020_305RC


335463.0


7880344.0






53.0


06-Dec-20


07-Dec-20


RC


MGA94_54




BO_2020_306RC


335395.0


7880283.0






107.0


08-Dec-20


08-Dec-20


RC


MGA94_54



 
TABLE B2: SUMMARY FROM INITIAL INSPECTION - BO_2020_301 TO 306 AT BIG ONE DEPOSIT 
 



Drillhole


Mineralised Zone


From (m, as drilled)


To (m, as drilled)


Thickness (m)


EOH DEPTH


Comments




BO_2020_301RC


1


28


31


3


53


Black copper oxides 




BO_2020_301RC


2


32


41


9


53


Black copper oxides & malachite




BO_2020_302RC


1


36


39


3


59


Black copper oxides 




BO_2020_303RC


1


25


28


3


53


Malachite, black copper oxides & azurite




BO_2020_303RC


2


28


35


7


53


Malachite and chalcocite 




BO_2020_304RC


1


81


82


1


107


Azurite & malachite




BO_2020_305RC


1


30


34


4


53


Malachite & chalcocite 




BO_2020_305RC


2


39


40


1


53


Chalcocite




BO_2020_306RC


1


93


97


4


107


Malachite & pyrite




BO_2020_306RC


2


99


102


3


107


Chalcocite



 
 




APPENDIX B: JORC CODE, 2012 EDITION - TABLE 1
The following JORC Code (2012 Edition) Table 1 is primarily supplied for the provision of the first release of data for the Big One Deposit.
Section 1 Sampling Techniques and Data



Criteria


JORC Code explanation


Commentary




Sampling techniques


·      Nature and quality of sampling (eg cut channels, random chips, or specific specialised industry standard measurement tools appropriate to the minerals under investigation, such as down hole gamma sondes, or handheld XRF instruments, etc). These examples should not be taken as limiting the broad meaning of sampling.
·      Include reference to measures taken to ensure sample representivity and the appropriate calibration of any measurement tools or systems used.
·      Aspects of the determination of mineralisation that are Material to the Public Report.
·      In cases where 'industry standard' work has been done this would be relatively simple (eg 'reverse circulation drilling was used to obtain 1 m samples from which 3 kg was pulverised to produce a 30 g charge for fire assay'). In other cases more explanation may be required, such as where there is coarse gold that has inherent sampling problems. Unusual commodities or mineralisation types (eg submarine nodules) may warrant disclosure of detailed information.


·      Reverse Circulation, RC, drilling and sampling techniques employed for the first 13 holes (of a 35-hole program) currently completed at the Big One Deposit by CCZ. 
·      Samples were taken off a cyclone for every metre drilled, put through a three tier, 87.5/12.5 splitter where approximately 2.5 kg of RC chip samples were collected for every metre drilled. The remainder was bagged separately and stored in case additional sub sampling is required soon.
·      Samples were also composited very four metres and all samples were collected to maximise optimal representation for each sample.
·      Each metre sample had an amount removed for washing and cleaning and sieving then place into metre allocated chip trays. These chips were logged on site by the rig geologists and those logs have been saved into a spreadsheet and stored on the Company server. Any visible mineralisation, alteration or other salient features were recorded in the logs. Industry wide, acceptable, standard practices were adhered to for the drilling and sampling of each metre as per the Drilling and Sampling Procedures set out before commencement of the drilling programme.




Drilling techniques


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


·      Reverse Circulation drilling used for first 13 holes at Big One Deposit.
·      The reader of the current ASX Release is referred to the CCZ's first publication of the geological diagrams and associated information: (1) "Final targets completed for drilling campaigns at Arya and Big One Deposit" released on the ASX by CCZ on the 14-July-2020. (2) "Field analysis verifies high-grade copper with newly identified gold mineralisation at Big One" released on the ASX by CCZ on the 14-Sep-2020.




Drill sample recovery


·      Method of recording and assessing core and chip sample recoveries and results assessed.
·      Measures taken to maximise sample recovery and ensure representative nature of the samples.
·      Whether a relationship exists between sample recovery and grade and whether sample bias may have occurred due to preferential loss/gain of fine/coarse material.


·      Within acceptable, industry standard limits, 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 effort was made on site to maximise recovery including cleaning out the sample trays, splitter and cyclone and ensuring that the drillers progressed at a steady constant rate in order for the rig to easily complete each metre effectively.




Logging


·      Whether core and chip samples have been geologically and geotechnically logged to a level of detail to support appropriate Mineral Resource estimation, mining studies and metallurgical studies.
·      Whether logging is qualitative or quantitative in nature. Core (or costean, channel, etc) photography.
·      The total length and percentage of the relevant intersections logged.


·      Every metre drilled and sampled was logged geologically in accordance with industry- wide acceptable standard for RC logging and the logging was qualitative in nature with every metre logged.




Sub-sampling techniques and sample preparation


·      If core, whether cut or sawn and whether quarter, half or all core taken.
·      If non-core, whether riffled, tube sampled, rotary split, etc and whether sampled wet or dry.
·      For all sample types, the nature, quality and appropriateness of the sample preparation technique.
·      Quality control procedures adopted for all sub-sampling stages to maximise representivity of samples.
·      Measures taken to ensure that the sampling is representative of the in situ material collected, including for instance results for field duplicate/second-half sampling.
·      Whether sample sizes are appropriate to the grain size of the material being sampled.


·      For the first 13 RC holes drilled by CCZ, samples were taken off a cyclone for every metre drilled, put through a three tier, 87.5/12.5 splitter where approximately 2.5 kg of RC chip samples were collected for every metre drilled. The remainder was bagged separately and stored in case additional sub sampling is required soon.
·      Samples were also composited outside of identified mineralised zones at 4 metres and all samples were collected to maximise optimal representation for each sample.
·      Each metre sample had an amount removed for washing and cleaning and sieving then place into metre allocated chip trays. These chips were logged on site by the rig geologists and those logs have been saved into a spreadsheet and stored on the Company server. Any visible mineralisation, alteration or other salient features were recorded in the logs. Industry wide, acceptable, standard practices were adhered to for the drilling and sampling of each metre as per the Drilling and Sampling Procedures set out before commencement of the drilling programme.




Quality of assay data and laboratory tests


·      The nature, quality and appropriateness of the assaying and laboratory procedures used and whether the technique is considered partial or total.
·      For geophysical tools, spectrometers, handheld XRF instruments, etc, the parameters used in determining the analysis including instrument make and model, reading times, calibrations factors applied and their derivation, etc.
·      Nature of quality control procedures adopted (eg standards, blanks, duplicates, external laboratory checks) and whether acceptable levels of accuracy (ie lack of bias) and precision have been established.


·      CCZ's first 13 RC holes have been assayed by an independent laboratory, ALS. Methods used were as follows:
·      Gold - by method Au-AA25 30g charge (fire Assay with AAS finish);
·      High gold values within oxide zone/supergene zone may need further testing by method Au-SCR21;
·      Copper and 32 other - by method ME-ICP61 (HF-HN03-HCL04 acid digest, HCL leach and ICP-AES finish);
·      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 widely considered as suitable and appropriate for this type of mineralisation.
·      For historical assaying, the assays were done by Independent Laboratory (ALS). All elements except for gold were analysed by method ME ICP41 (35 element testing via Aqua Regia digest then ICP-AES) and with many copper assays greater than 1%, the copper was redone using method Cu-OG46 with ICP-AES. The gold was done by fire assay method AA25. All methods used were both suitable and appropriate for the styles of mineralisation present in the Big One Deposit.




Verification of sampling and assaying


·      The verification of significant intersections by either independent or alternative company personnel.
·      The use of twinned holes.
·      Documentation of primary data, data entry procedures, data verification, data storage (physical and electronic) protocols.
·      Discuss any adjustment to assay data.


·      CCZ's first four (4) RC hole assay results from ALS have been reviewed by two independent consultant geologists.
·      For historical drilling, Independent Laboratory assaying by ALS has confirmed, within acceptable limits, the occurrences of high-grade copper inferred from the initial XRF readings. Laboratory standards and duplicates were used in accordance with standard procedures for geochemical assaying. For the first seven holes of the current drilling programme, ALS has confirmed the copper assay results that were greater than 10 000 pppm or 0.1% Cu.




Location of data points


·      Accuracy and quality of surveys used to locate drill holes (collar and down-hole surveys), trenches, mine workings and other locations used in Mineral Resource estimation.
·      Specification of the grid system used.
·      Quality and adequacy of topographic control.


·      The first 13 RC holes done by CCZ have had their location surveyed by GPS and these have now been surveyed by differential GPS by independent licensed surveyors.
·      The spatial location for the first seven holes have been differentially surveyed into the National Grid System.




Data spacing and distribution


·      Data spacing for reporting of Exploration Results.
·      Whether the data spacing and distribution is sufficient to establish the degree of geological and grade continuity appropriate for the Mineral Resource and Ore Reserve estimation procedure(s) and classifications applied.
·      Whether sample compositing has been applied.


·      The first 13 RC holes were part of a 35-hole program that was set out on a nominal 50m pattern. At the completion of all the planned holes, the drillhole collars will be differentially surveyed by independent, licensed surveyors and the grid pattern verified.
·      The spatial location for the photographs collected during the preliminary site visit at the Big One Deposit were collected at two previously mined sites that exposed the copper mineralisation. The preliminary site visit was brief, in a limited time inspection of the Big One Deposit with the Landholder, therefore the full 600m strike length of the surface mineralisation is yet to be observed, the observations completed on the 05-August-2020 showed prospective copper mineralisation within one of the mined pits and the greater Big One Deposit area is anticipated to undergo a widespread reconnaissance during the pegging of the Big One Deposit drill sites.
·      The 05-August-2020 observed mineralisation included:
o  Location 01 (Figure 1, left photo, in ASX Release body): View looking east-northeast in the main excavated pit at the Big One Mine sub-parallel to the strike of the mineralisation, steep dip to the south-east dipping, which includes a copper carbonate mineralised fault breccia zone; 
o  Location 02 (Figure 1, right photo, in ASX Release body):  View looking west-south-west, the same sub-vertical structure looking south in a second pit following the strike trend in the opposite direction to the first pit; the host sediments are strongly hematite stained (non-magnetic), it is possible the mineralisation had been fully excavated here;
o  Location 03 (Figure 2, left photo, in ASX Release body):   Malachite (green) and Azurite (blue) as staining and fracture fill in this case, in fault brecciated siltstone. Most likely this had spalled off the mineralised zone, located as in pit float material. Green malachite and blue azurite are common as breccia and slicken side fracture fill; and 
o  Location 04 (Figure 2, right photo, in ASX Release body):   Malachite (green) as a crystalline coating/fracture infill on haematite-stained siltstone. Most likely this had spalled off the mineralised zone, located as in pit float material.




Orientation of data in relation to geological structure


·      Whether the orientation of sampling achieves unbiased sampling of possible structures and the extent to which this is known, considering the deposit type.
·      If the relationship between the drilling orientation and the orientation of key mineralised structures is considered to have introduced a sampling bias, this should be assessed and reported if material.


·      The current CCZ RC drilling programme has had all holes oriented to intersect the mineralised structure/zone subsurface perpendicularly and therefore does not constitute any perceived bias.
·      Rock chip samples were taken at areas of interest from observed mineralisation along the line of lode of the mineralised dyke, secondary structures, and surrounding spoil heaps.




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




Audits or reviews


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


·      This will be done once all 35 holes in CCZ's program are completed.
·      For the historical drilling, the sampling techniques and the data generated from the Laboratory Assay results have been peer reviewed by consultant geologists familiar with the overall Mt Oxide Project and deemed to be acceptable.



 




 
Section 2 Reporting of Exploration Results
(Criteria listed in the preceding section also apply to this section.)



Criteria


JORC Code explanation


Commentary




Mineral tenement and land tenure status


·      Type, reference name/number, location and ownership including agreements or material issues with third parties such as joint ventures, partnerships, overriding royalties, native title interests, historical sites, wilderness or national park and environmental settings.
·      The security of the tenure held at the time of reporting along with any known impediments to obtaining a licence to operate in the area.


·      The following mineral tenures are held 100% by subsidiaries of Castillo Copper Limited, totalling an area of 736.8 km2 in the "Mt Oxide project":
o  EPM 26574 (Valparaisa North) - encompasses the Big One historical mineral resource, Holder Total Minerals Pty Ltd, Granted 12-June-2018 for a 5 year period over 100 sub-blocks (323.3Km2), Expires 11-June-2023;
o  EPM 26462 (Big Oxide North) - encompasses the 'Boomerang' historical mine and the 'Big One' historical mine, Holder: QLD Commodities Pty Ltd, Granted: 29-Aug-2017 for a 5 year period over 67 sub-blocks (216.5Km2), Expires: 28-Aug-2022; 
o  EPM 26525 (Hill of Grace) - encompasses the Ayra significant aeromagnetic anomaly, Holder: Total Minerals Pty Ltd for a 5 year period over 38 sub-blocks (128.8Km2), Granted: 12-June-2018, Expires: 11-June-2023;
o  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
o  EPMA 27440 (The Wall) - An application lodged on the 12-Dec-2019 over 70 sub-blocks (~215Km2) by Castillo Copper Limited.
·      A check on the tenures in 'application status' was completed in 'GeoResGlobe' on the 23rd-September-2020.  




Exploration done by other parties


·      Acknowledgment and appraisal of exploration by other parties.


·      Historical QDEX / mineral exploration reports have been reviewed for historical tenures that cover or partially cover the Project Area in this announcement. Federal and State Government reports supplement the historical mineral exploration reporting (QDEX open file exploration records).
·      Most explorers were searching for Cu-Au-U, and in particular, proving satellite deposit style extensions to the several small sub-economic copper deposits (e.g. Big Oxide and Josephine).
·      With the Mt Oxide Project in regional proximity to Mt Isa and numerous historical and active mines, the Project area has seen portions of the historical mineral tenure subject to various styles of surface sampling, with selected locations typically targeted by shallow drilling (Total hole depth is typically less than 50m).
·      The Mt Oxide project tenure package has a significant opportunity to be reviewed and explored by modern exploration methods in a coherent package of EPM's, with three of these forming a contiguous tenure package.
·      Various Holders and related parties of the 'Big One' historical mining tenure (ML8451) completed a range of mining activities and exploration activities on what is now the 'Big One' prospect for EPM 26462. The following unpublished work is acknowledged (and previously shown in the reference list): 
o  West Australian Metals NL, 1994. Drill Programme at the "Big One" Copper Deposit, North Queensland for West Australian Metals NL. 
o  Wilson, D., 2011. 'Big One' Copper Mine Lease 5481 Memorandum - dated 7 May 2011.
o  Wilson, D., 2015. 'Big One' Mining Lease Memorandum - dated 25 May 2015: and
o  Csar, M, 1996. Big One & Mt Storm Copper Deposits. Unpublished field report.
·      The reader of the current ASX Release is referred to the CCZ's first publication of the 1993 historical reverse circulation drilling results for additional diagrams and drilling information: "Historic drill data verifies grades up to 28.40% Cu from <50m in supergene ore at Mt Oxide Pillar" released on the ASX by CCZ on the 14-January-2020.
·      The reader of the current ASX Release is referred to the CCZ's first publication of the geological diagrams and associated information: "Drill program finalised to test 130m massive sulphide target at Arya prospect in Mt Oxide Pillar" released on the ASX by CCZ on the 1-July-2020. 
·      The reader of the current ASX Release is referred to the CCZ's first publication of the geological diagrams and associated information: (1) "Final targets completed for drilling campaigns at Arya and Big One Deposit" released on the ASX by CCZ on the 14-July-2020. (2) "Field analysis verifies high-grade copper with newly identified gold mineralisation at Big One" released on the ASX by CCZ on the 14-Sep-2020.
·      The SRK Independent Geologists Report released by CCZ on the ASX on 28-July-2020 contains further details on the 'Exploration done by other parties - Acknowledgment and appraisal of exploration by other parties' this report is formally titled "A Competent Persons Report on the Mineral Assets of Castillo Copper Limited" Prepared as part of the Castillo Copper Limited (ASX: CCZ, LSE: CCZ) LSE Prospectus, with the effective date of the 17-July-2020. 




Geology


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


·      The Mt Oxide North project is located within the Mt Isa Inlier of western Queensland, a large, exposed section of Proterozoic (2.5 billion- to 540-million-year-old) crustal rocks. The inlier records a long history of tectonic evolution, now thought to be like that of the Broken Hill Block in western New South Wales.
·       The Mt Oxide 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 Project area is cut by a major fault zone, trending north- northeast - south- southwest across the permits. This fault is associated with major folding, forming several tight syncline- anticline structures along its length.
·      The Desktop studies commissioned by CCZ on the granted mineral tenures described four main styles of mineralisation account for most mineral resources within the rocks of the Mt Isa Province (after Withnall & Cranfield, 2013). 
o  Sediment hosted silver-lead-zinc - occurs mainly within fine-grained sedimentary rocks of the Isa Super basin within the Western Fold Belt. Deposits include Black Star (Mount Isa Pb-Zn), Century, George Fisher North, George Fisher South (Hilton) and Lady Loretta deposits. 
o  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. 
o  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
o  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."):
o  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 (062o to 242o) that is intruded by a porphyry dyke.
o  The mineralised porphyry dyke is vertical to near vertical (85o), 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.
o  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.
o  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 
o  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
o  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).
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
·      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. 
·      The SRK Independent Geologists Report released by CCZ on the ASX on 28-July-2020 contains further details on the 'Geology - Deposit type, geological setting and style of mineralisation': this report is formally titled "A Competent Persons Report on the Mineral Assets of Castillo Copper Limited" Prepared as part of the Castillo Copper Limited (ASX: CCZ, LSE: CCZ) LSE Prospectus, with the effective date of the 17-July-2020.




Drill hole Information


·      A summary of all information material to the understanding of the exploration results including a tabulation of the following information for all Material drill holes:
o  easting and northing of the drill hole collar
o  elevation or RL (Reduced Level - elevation above sea level in metres) of the drill hole collar
o  dip and azimuth of the hole
o  down hole length and interception depth
o  hole length.
·      If the exclusion of this information is justified on the basis that the information is not Material and this exclusion does not detract from the understanding of the report, the Competent Person should clearly explain why this is the case.


·      For CCZ's current drilling program. This information has been recorded during the drilling and will be checked and verified at the conclusion of the current program.




Data aggregation methods


·      In reporting Exploration Results, weighting averaging techniques, maximum and/or minimum grade truncations (eg cutting of high grades) and cut-off grades are usually Material and should be stated.
·      Where aggregate intercepts incorporate short lengths of high grade results and longer lengths of low grade results, the procedure used for such aggregation should be stated and some typical examples of such aggregations should be shown in detail.
·      The assumptions used for any reporting of metal equivalent values should be clearly stated.


·      Only 4 of 13 drillholes' assay has been completed on CCZ's current drilling program.
·      For historical drilling, Independent Laboratory Assay results for the 24 rock chip samples from the Big One Deposit were averaged if more than one reading or determination was given. There was no cutting of high-grade copper results as they are directly relatable to high grade mineralisation styles readily visible in the relevant samples. There was no cut-off grades factored into any assay results.




Relationship between mineralisation widths and intercept lengths


·      These relationships are particularly important in the reporting of Exploration Results.
·      If the geometry of the mineralisation with respect to the drill hole angle is known, its nature should be reported.
·      If it is not known and only the down hole lengths are reported, there should be a clear statement to this effect (eg 'down hole length, true width not known').


·      Rock chip samples were taken at areas of interest from observed mineralisation along the line of lode of the mineralised dyke, secondary structures and surrounding spoil heaps. 
·      8 rock chip samples collected from rock faces and/or outcrops.
·      16 rock chip samples collected from stockpiles, shaft waste piles, and/or boulders of rock onsite.
·      The reader of the current ASX Release is referred to the CCZ's first publication of the geological diagrams and associated information: (1) "Final targets completed for drilling campaigns at Arya and Big One Deposit" released on the ASX by CCZ on the 14-July-2020. (2) "Field analysis verifies high-grade copper with newly identified gold mineralisation at Big One" released on the ASX by CCZ on the 14-Sep-2020.




Diagrams


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


·      This part will be done once CCZ's current drilling program is completed and all samples have been assayed and verified.
·      Appropriate diagrams are presented in the body and the Appendices of the current ASX Release. Where scales are absent from the diagram, grids have been included and clearly labelled to act as a scale for distance. 
·      Maps and Plans presented in the current ASX Release are in MGA94 Zone 54, Eastings (mN), and Northing (mN), unless clearly labelled otherwise.




Balanced reporting


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


·      This part will be done once CCZ's current drilling program is completed and all samples have been assayed and verified.
·      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. 
·      Rock chip samples were taken at areas of interest from observed mineralisation along the line of lode of the mineralised dyke, secondary structures and surrounding spoil heaps. 
·      8 rock chip samples collected from rock faces and/or outcrops. A statistical summary of the rock chip sample assay results is presented below:







Cu (%)


Co (ppm)


Ag (ppm)


Au (ppm)




Minimum


0.72


8.0


0.30


0.010




Maximum


3.18


71.0


0.80


0.030




Average 


1.69


23.3


0.52


0.017




Count


8


8


5


3



 
·      16 rock chip samples collected from stockpiles, shaft waste piles, and/or boulders of rock onsite. A statistical summary of the 16-rock chip sample assay results are presented below:







Cu (%)


Co (ppm)


Ag (ppm)


Au (ppm)




Minimum


0.68


6.00


0.40


0.01




Maximum


33.20


267.00


27.30


0.20




Average 


9.29


84.94


3.68


0.07




Count


16


16


12


10








Other substantive exploration data


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


·      No other ground or airborne geophysical surveys have been undertaken to date. Bulk density testing is yet to be carried out.




Further work


·      The nature and scale of planned further work (eg tests for lateral extensions or depth extensions or large-scale step-out drilling).
·      Diagrams clearly highlighting the areas of possible extensions, including the main geological interpretations and future drilling areas, provided this information is not commercially sensitive.


·      'Further work' is described within the body of the ASX Release.



 
 

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