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CORE LITHIUM LTD — Regulatory Filings 2015
Jan 22, 2015
64737_rns_2015-01-22_be03ab33-c2fd-4314-9e7b-db5ac8afa11d.pdf
Regulatory Filings
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ASX ANNOUNCEMENT
ASX : CXO
23[rd] January 2015
Drill results received for Virginia and Copper Royals
HIGHLIGHTS
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Results for the Virginia and Copper royals received from Core’s preliminary RC drill program completed in late 2014
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Core’s drilling has intersected elevated copper related to chargeable IP targets at Virginia
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Drill results have confirmed presence of inconsistently mineralised structure at depth at Virginia, below surface geochemical anomalism
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Anomalous copper and zinc levels in drilling, but no zones of significant mineralisation identified
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Core will now move its immediate focus onto the Jervois Domain Project : final AEM data expected in the next few days
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Analysis and modelling of the Jervois Domain AEM data will be used to prioritise and refine targets prior to drill testing planned in March 2015
Core Exploration Ltd (ASX:CXO) has received all RC drill results from its recent reverse circulation (RC) drilling at its Virginia Prospect and Copper Royals district in the Northern Territory.
Core completed the Company’s first drilling program at the Virginia Prospect in late 2014 in an area never drilled before. Core’s RC drilling at Virginia was aimed at testing the source of the elevated copper in outcrop and soil geochemistry mapped for over 1.5 km of strike at Virginia.
Twelve RC holes were drilled at the Virginia Prospect and six RC holes at Copper Royals for a total of 1,745 metres to depths up to 120 metres (Figures and Tables 1 & 2).
Drilling at Virginia tested the IP chargeability anomalies from Core’s 2014 IP survey along two traverses and tested the peak of the preliminary Channel 25 conductive anomaly that is coincident with the central section of the Virginia Prospect.
A Level 2, 143 Hutt St, Adelaide SA 5000 | T (08) 7324 2987 | F (08) 8312 2002 | E [email protected] www.coreexploration.com.au
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Drill results have confirmed an inconsistently mineralised structure at depth at Virginia below surface geochemical anomalism related to the chargeable zones in Core’s previous IP geophysics. Downhole geology is interpreted as cyclical sequences of variably garnet and silica altered Riddock Amphibolite that dip approximately 10°‐20° to the northwest.
Core’s drilling at Virginia has intersected sulphide mineralisation comprising fracture filling and disseminated pyrite (iron sulphide) which is common throughout and localised chalcopyrite (copper sulphide). Malachite and azurite (copper carbonate) minerals extend from surface to 10‐20m metres depth.
Core also completed a reconnaissance drilling program at Copper Royals to follow on from the Virginia drilling program to test new targets with a single hole to determine potential for future follow‐up. Occasional anomalous levels of copper and zinc were intersected by drilling at the Copper Royals, but no significant mineralised zones were intersected in drilling.
An increase of sulphides around coarse‐grained garnet porphyroblasts was evident in some holes, which accounts for the chargeable IP anomalies, but was variable and therefore challenging to define favourable mineralised stratigraphic layering.
It is suggested that hydromorphic mobilisation of copper from the amphibolite package at Virginia and Copper Royals has brought elevated levels of copper to the surface that outcrops as distinct copper carbonates. This process seems to be in contrast to Core’s previous drill results at Inkheart 40km to the south, where drilling intersected a consistently mineralised sulphide system at depth.
The Company will now focus on the Jervois Project and anticipate receiving final AEM results in the next week. The analysis and modelling of the new AEM data will be utilised to prioritise and refine targets prior to drill testing planned to commence in March 2015.
For further information please contact:
| Stephen Biggins Managing Director Core Exploration Ltd 08 7324 2987 [email protected] |
John Field Field Public Relations 08 8234 9555 [email protected] |
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The information in this report that relates to Exploration Results and Mineral Resources is based on information compiled by Stephen Biggins (BSc(Hons)Geol, MBA) as Managing Director of Core Exploration Ltd who is a member of the Australasian Institute of Mining and Metallurgy and is bound by and follows the Institute’s codes and recommended practices. He has sufficient experience which is relevant to the styles of mineralisation and types of deposits under consideration and to the activities being undertaken to qualify as a Competent Person as defined in the 2012 Edition of the “Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves”. Mr. Biggins consents to the inclusion in the report of the matters based on his information in the form and context in which it appears . This report also references information previously released under JORC Code 2012 to the ASX on 23/12/2014 “Elevated copper in early stage drilling from Virginia”.
A Level 2, 143 Hutt St, Adelaide SA 5000 | T (08) 7324 2987 | F (08) 8312 2002 | E [email protected] www.coreexploration.com.au
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Figure 1. Drilling results and collar locations overlain on geology, Virginia Prospects, NT.
Virginia Prospect Discussion
The twelve drill holes at Virginia were primarily designed to test a number of chargeable anomalies identified in the Induced Polarisation survey CXO collected in early 2014 which indicated a shallow north westerly dip to a potentially mineralised sequence of Riddock Amphibolite.
Two drilling traverses were completed and in addition two holes were targeted under the central portion of the surface geochemical anomaly where visible malachite and azurite staining is common in outcrop.
Geologically, Virginia comprises cyclical sequences of Riddock Amphibolite with variable coarse‐ grained garnet and silica alteration that overlie biotite‐plagioclase‐quartz gneiss and minor calc‐ silicate units of the Lower Harts Range Group.
Unfortunately the results overall were disappointing with the chargeable features explained by disseminated and fracture coatings of pyrite (iron sulphide). Whilst a few significant copper intersections were encountered on the westerly traverse as reported (ASX 23/12/14) the eastern traverse and central holes did not return any significant intersections and only showed inconsistent broad zones of very weakly elevated copper and zinc.
A Level 2, 143 Hutt St, Adelaide SA 5000 | T (08) 7324 2987 | F (08) 8312 2002 | E [email protected] www.coreexploration.com.au
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Copper Royals Discussion
Core planned a six hole reconnaissance drilling program to follow on from the Virginia drilling program to test new targets in the Copper Royals district with a single reconnaissance hole to determine potential for future follow‐up.
Prior to drilling, Core conducted a re‐evaluation of the previous exploration work by Tanami Gold, who drilled 230 RAB holes (6,843m) in 2002. The re‐evaluation highlighted that the majority of the surface geochemical anomalies were adequately tested which included extensive drilling at Copper King and Copper Queen Prospects to depths approaching 100 metres.
Also of note within the Copper Royals district, access can be a constraining factor due to very rugged terrain with extreme relief.
Anomalous levels of copper and zinc were intersected by drilling at the Copper Royals, but no significant mineralised zones were interested in drilling.
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Figure 2: Collar Plan of Copper Royals Drilling Program
A Level 2, 143 Hutt St, Adelaide SA 5000 | T (08) 7324 2987 | F (08) 8312 2002 | E [email protected]
www.coreexploration.com.au
| Hole_ID | Easting | Northing | RL | DIP | Azimuth | Total Depth | |
| VGRC001 | 476465 | 7444684 | 685 | ‐90 | 0 | 120 | |
| VGRC002 | 476539 | 7444598 | 691 | ‐90 | 0 | 110 | |
| VGRC003 | 476661 | 7444533 | 699 | ‐90 | 0 | 120 | |
| VGRC004 | 476720 | 7444431 | 694 | ‐90 | 0 | 108 | |
| VGRC005 | 477279 | 7444411 | 712 | ‐70 | 350 | 99 | |
| VGRC006 | 477422 | 7444424 | 704 | 70 | 3 | 99 | |
| ‐ | 55 | ||||||
| VGRC007 | 477549 | 7444499 | 698 | ‐90 | 0 | 51 | |
| VGRC008 | 477480 | 7444643 | 699 | ‐90 | 0 | 120 | |
| VGRC009 | 477406 | 7444734 | 692 | ‐90 | 0 | 108 | |
| VGRC010 | 477353 | 7444853 | 684 | ‐90 | 0 | 99 | |
| VGRC011 | 477288 | 7444943 | 677 | ‐90 | 0 | 99 | |
| VGRC012 | 477247 | 7445049 | 665 | ‐90 | 0 | 120 | |
| Total Metres: | 1253 |
Table 1: Virginia Reverse Circulation Drill Hole Information
| Hole ID | Easting | Northing | RL | Dip | Azimuth | Total Depth |
|---|---|---|---|---|---|---|
| CRRC001 | 464932 | 7442322 | 738 | ‐70 | 45 | 84 |
| CRRC002 | 466641 | 7440094 | 753 | ‐90 | 0 | 105 |
| CRRC003 | 467120 | 7440253 | 763 | ‐90 | 0 | 84 |
| CRRC004 | 466099 | 7441561 | 750 | ‐70 | 001 | 60 |
| CRRC005 | 466769 | 7440770 | 748 | ‐60 | 195 | 81 |
| CRRC006 | 465768 | 7439667 | 762 | ‐90 | 0 | 78 |
Table 2: Copper Royal Drill Hole Information
A Level 2, 143 Hutt St, Adelaide SA 5000 | T (08) 7324 2987 | F (08) 8312 2002 | E [email protected] www.coreexploration.com.au
Virginia and Copper Royals RC Drilling – November 2014– JORC 2012 Section 1 Sampling Techniques and Data
(Criteria in this section apply to all succeeding sections.)
| 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 (egg ‘RC 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 (egg submarine nodules) may warrant disclosure of detailed information. |
All RC drill cuttings were spear sampled. All drilled intervals were sampled as 3-metre composites with samples collected using a spear Each one metre drilled interval is qualitatively annotated with a sample quality based on weight and moisture content. |
| Drilling techniques |
Drill type (e.g. core, RC, open-hole hammer, rotary air blast, auger, Bangka, sonic, etc) and details (e.g. core diameter, triple or standard tube, depth of diamond tails, face-sampling bit or other type, whether core is oriented and if so, by what method, etc). |
Bullion Drilling were contracted to undertake RC drilling All drilling was face sampling with a 4” Slimline RC Hammer The majority of RC drilling was drilled vertically. VGRC005 and VGRC006 were drilled at -70 to the north. No downhole surveys were undertaken |
| Drill sample recovery |
Method of recording and assessing core and chip sample recoveries and results assessed. Measures taken to maximise sample recovery and ensure |
A visual estimate of recovery over individual one-metre drilled estimates was recorded. RC drilling only so no assessment of sample representivity or sample bias available. |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| 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. |
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| 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. |
Drill cuttings are qualitatively logged and photographed Qualitative logging includes lithology, colour, mineralogy, description, marker horizons, weathering, texture, alteration and mineralization |
| 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. |
See sampling section above for a description of sampling and sub- sampling techniques. Sample sizes are considered appropriate for the expected grainsize of mineralisation. Every twentieth sample submitted for analysis was sampled was duplicated. Certified standards were submitted in sequence for every 25 samples submitted. Subsampling techniques are undertaken in line with standard operating practices in order to ensure no bias associated with sub- sampling. The nature, quality and appropriateness of the sampling technique is considered adequate for the type of mineralisation and confidence level being attributed to this initial reconnaissance drilling program. |
| 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 |
A certified and accredited global laboratory (Intertek-Genalysis) was used for all assays. Sample preparation was undertaken in Alice Springs with analysis undertaken at Intertek’s Adelaide laboratory. |
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| Criteria | JORC Code explanation | Commentary | Commentary |
|---|---|---|---|
| make and model, reading times, calibrations factors applied and their derivation, etc. Nature of quality control procedures adopted (e.g. standards, blanks, duplicates, external laboratory checks) and whether acceptable levels of accuracy (i.e. lack of bias) and precision have been established. |
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Samples were analysed using Intertek’s 4A/OM10 technique which involves near-total 4 acid digest and analysis using ICP-OES and ICP-MS for 46 elements. In addition gold was analysed using a 25g fire-assay / AAS technique Internal certified laboratory QAQC is undertakenby Intertek. Duplicates and certified standards were inserted in sequence as detailed above. |
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| 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. |
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Primary data is captured directly into an in-house referential and integrated database system designed and managed by the Exploration Manager. All assay data is cross-validated within the database by various integrity scripts and externally using MapInfo drill hole validation checks including interval integrity checks. Laboratory assay data is not adjusted. |
| 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. |
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Collar co-ordinate surveys All coordinates are recorded in GDA 94 MGA Zone 53. Surveys have been undertaken by Core Exploration staff using a hand-held GPS this tool has an accuracy of approximately 3m. Topographic control uses the DTM generated by the VTEM 200m airborne survey recently conducted over the Virginia Prospect Down hole surveys No downhole surveys were undertaken |
| 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. |
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Initial reconnaissance RC drilling only. See drilling section above regarding composite sampling |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| Whether sample compositing has been applied. | ||
| 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. |
Initial reconnaissance drilling only |
| Sample security |
The measures taken to ensure sample security. | Sample Intervals are put into individually numbered calico sample bags and are then loaded into cable tied bulka-bags before being dispatched to Intertek-Alice Springs for sample preparation. Assay pulps are returned to Core Exploration from contracted laboratories on a regular basis and stored securely for future reference. |
| Audits or reviews |
The results of any audits or reviews of sampling techniques and data. | No audits or reviews have been undertaken |
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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 Virginia and Copper Royals prospect areas is contained within EL 29689 that is 100% held by DBL Blues Pty Ltd a wholly owned subsidiary of Core Exploration Ltd. Core Exploration manages EL 29689. EL 29689 is located on Mt Riddock Station. All drilling was undertaken outside of Heritage, Conservation or National Parks on EL 28136. All work was undertaken within the scope of the Exploration Mining Management Plan (EMMP) that was approved by NTDME |
| Exploration done by other parties |
Acknowledgment and appraisal of exploration by other parties. | Historical exploration is limited to surface rockchip and soil geochemistry. In 2014 CXO collected two lines of dipole-dipole IP and flew a VTEM supermax AEM survey |
| Geology | Deposit type, geological setting and style of mineralisation. | Geology comprises Proterozoic geology of the Harts Range Group including the Riddock Amphibolite Member and Naringa Calc-silicate Member and Bruna Gneiss. Drilling is targeting Cu mineralisation. |
| 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 collaro elevation or RL (Reduced Level – elevation above sea level inmetres) of the drill hole collar o dip and azimuth of the holeo down hole length and interception deptho hole length. |
Drill hole information is recorded within the CXO in-house database with all collar locations listed in the table accompanying this document. No material information is excluded. |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| 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. |
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| Data aggregation methods |
In reporting Exploration Results, weighting averaging techniques, maximum and/or minimum grade truncations (e.g. cutting of high grades) and cut-off grades are usually Material and should be stated. Where aggregate intercepts incorporate short lengths of high grade results and longer lengths of low grade results, the procedure used for such aggregation should be stated and some typical examples of such aggregations should be shown in detail. The assumptions used for any reporting of metal equivalent values should be clearly stated. |
Aggregated intersections have been calculated for copper and lead using a 0.1% cut-off. Minimum intersection widths are 3m and up to 3m of internal dilation are included No metal equivalents are reported. |
| Relationship between mineralisatio n widths and intercept lengths |
These relationships are particularly important in the reporting of Exploration Results. If the geometry of the mineralisation with respect to the drill hole angle is known, its nature should be reported. If it is not known and only the down hole lengths are reported, there should be a clear statement to this effect (e.g. ‘down hole length, true width not known’). |
Initial reconnaissance drilling only thus geometric relationship of mineralisation to vertical drill orientation unknown. |
| 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. |
See attached plans showing drill hole density and sections as well as the tabulated drill hole information data accompanying this document. |
| 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. |
See attached table of intersections. Reported intersections use the criteria detailed in the above section “data aggregation methods”. |
| 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. |
Due to the drilling technique primary textures are hard to distinguish or are obliterated. Significant groundwater was present in VGRC002 and VGRC003 below 50m depth. Multi-element geochemistry assaying (47 elements) including gold by fire-assay is routine for all sampling. Some elemental associations are recognised within certain lithologies within the region and are |
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| Criteria | JORC Code explanation | Commentary |
|---|---|---|
| used as a tool to assist in interpretation of original lithologies where alteration affected the ability to visually determine the lithology. |
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| Further work | The nature and scale of planned further work (e.g. tests for lateral extensions or depth extensions or large-scale step-out drilling). Diagrams clearly highlighting the areas of possible extensions, including the main geological interpretations and future drilling areas, _provided this information is not commercially sensitive. _ |
Subject to Board approval further drilling may be undertaken |
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