REG - Rockfire Resources - Maiden Resource at Copperhead
21/03/2022 07:15
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RNS Number : 3641F Rockfire Resources PLC 21 March 2022
The information contained within this announcement is deemed by the Company to
constitute inside information as stipulated under the Market Abuse Regulations
(EU) No. 596/2014 ("MAR"") (which forms part of domestic UK law pursuant to
the European Union (Withdrawal) Act 2018). With the publication of this
announcement via a Regulatory Information Service, this inside information is
now considered to be in the public domain.
21 March 2022
Rockfire Resources plc
("Rockfire" or the "Company")
Maiden Resource at Copperhead Confirms Large Mineral System
Rockfire Resources plc (LON: ROCK), the gold and base metal exploration
company, is pleased to announce that the Company's 100% owned Copperhead
Cu-Mo-Ag Deposit in Queensland, Australia, has delivered a maiden JORC (2012)
Mineral Resource of 120,000 tonnes of copper equivalent.
Highlights
· Mineral Resource of 64 million tonnes @ 0.19 % Cu EQ ( 1 ) for
120,000 tonnes of Cu Eq. in the Inferred category.
Mineral Resource Statement (effective date 14th March 2022)
Cut-off (Grade Cu Eq %) Resource Category Tonnage (Mt) Grade Contained Metal
Cu Eq % Cu % Mo % Ag (g/t) Cu Eq (Kt) Cu (Kt) Mo (Kt) Ag (M oz)
0.13 Inferred 64 0.19 0.12 0.015 0.55 120 80 9.4 1.1
· The mineral resource remains open to the north, east, west and at
depth, leaving scope for significant, further resource increases.
· This resource comprises five diamond drill holes drilled by Rockfire,
which were designed to validate historical drilling results and to attain a
JORC resource. Both aims have been comprehensively accomplished.
· The extent and tenor of mineralisation at Copperhead have yet to be
fully tested. Copper mineralisation starts at surface and continues for at
least 400 m vertically below surface.
· With continued exploration success and expansion of the resource,
Copperhead demonstrates potential to form a low-cost, bulk-tonnage, open cut
mining scenario.
· The copper price remains robust with the continued strong demand for
electric vehicles and green energy, including wind turbines and solar panels.
· Copperhead is situated approximately 250 km by road from Australia's
largest copper smelter near Townsville.
An oblique cross section through the drilling at Copperhead can be viewed by
following this link.
http://www.rns-pdf.londonstockexchange.com/rns/3641F_1-2022-3-20.pdf
(http://www.rns-pdf.londonstockexchange.com/rns/3641F_1-2022-3-20.pdf)
David Price, Chief Executive Officer of Rockfire, commented:
"We are delighted to have delivered this maiden resource on time and within
budget. It was a primary aim of the Company to realise a maiden copper
resource at Copperhead and I congratulate the team on the dedication they have
put into achieving this milestone. Rockfire has JORC gold resources, JORC
silver resources and now a JORC copper resource in its portfolio, creating
diverse material value across the Company's project base.
"This maiden resource highlights the potential size of Copperhead, with each
hole intersecting copper over varying intervals. Some of the impressive
intervals encountered during the maiden drill programme include 501 m @ 0.14%
CuEq., 357 m @ 0.11% CuEq., 185 m @ 0.20% CuEq. and 370 m @ 0.20% CuEq.
Higher-grade copper values were encountered up to a peak of 2.28% Cu in
individual, metre-long samples.
"This is a great start for Copperhead and more resources are expected to be
discovered to the north, east, west and at depth. A northeast preferred
structural orientation remains open, with highly anomalous soil samples
vectoring towards a regional-scale gravity low. More than 3,000 copper-bearing
veins have been measured in core, with many of the veins hosting
sericite/muscovite alteration and quartz. This suggests drilling has occurred
in the upper (quartz/sericite) levels of a classic porphyry system and above
the porphyry source itself.
"Rockfire's inaugural drilling programme at Copperhead was designed to
validate the historical drilling from 1972. During our recent drilling, the
extent of copper mineralisation was expanded beyond the historical drilling
limits and grades were sampled and confirmed throughout the entirety of each
hole, rather than selective and sporadic interval sampling, as was the
methodology in 1972.
"Copperhead now shows promising signs of being a significant copper discovery.
Rockfire has drilled five holes to achieve a maiden Inferred Resource and
further drilling is expected to increase the footprint of mineralisation,
providing increased tonnage to an already impressive 64.0 million tonnes. The
eventual size of Copperhead is yet to be defined.
"Rockfire is in an enviable position of being well-funded and with cumulative
JORC resources in Queensland of:
· 130,000 ounces of gold at Plateau
· 800,000 ounces of silver at Plateau
· 120,000 tonnes of copper equivalent at Copperhead (comprising 80,000
tonnes of copper, 9,000 tonnes of molybdenum and 1.1 million ounces of
silver).
"Rockfire's management is very pleased with the progress being made by the
Company across its portfolio and we wish to thank all our shareholders for
their continued support as we create and sustain further value in our
projects. The continued addition of mineral resources to our Company builds
value and ultimately shareholder wealth. I would like to emphasise that
Rockfire has sufficient funding to maintain our current exploration momentum.
We will continue to keep the market up to date as our work progresses."
Qualified Person Statement:
Information in this announcement that relates to exploration results and the
Mineral Resource Estimate is based on information compiled by Mr Edward Fry,
the Exploration Manager of Rockfire Resources plc, who is a Member of the
Australasian Institute of Mining and Metallurgy (MAusIMM). Mr Fry has
sufficient experience relevant to the style of mineralisation and type of
deposit under consideration and to the activity which has been undertaken to
qualify as a Competent Person as defined by the 2012 Edition of the
Australasian Code for Reporting of Exploration Results, Mineral Resources and
Ore Reserves (the JORC Code) and a "Qualified Person" in accordance with the
AIM Rules Guidance Note for Mining and Oil & Gas Companies. Mr Fry
consents to the inclusion in the announcement of the matters based on their
information in the form and context in which it appears.
For further information on the Company, please
visit www.rockfireresources.com (http://www.rockfireresources.com/) or
contact the following:
Rockfire Resources plc: info@rockfireresources.com
David Price, Chief Executive Officer
Allenby Capital Limited (Nominated Adviser & Broker) Tel: +44 (0) 20 3328 5656
John Depasquale / George Payne (Corporate Finance)
Matt Butlin / Kelly Gardner (Sales and Corporate Broking)
Yellow Jersey rockfire@yellowjerseypr.com
Sarah Hollins / Henry Wilkinson Tel: +44 (0) 20 3004 9512
Notes to Editors
Rockfire Resources plc (LON: ROCK) is an exploration company with a portfolio
of 100%-owned near-surface gold and large-scale copper projects in Queensland,
Australia. The gold project is located within 50 km of two operating gold
mines and the Company's copper projects lie within 250 km of Australia's
largest copper refinery.
The Plateau Gold Deposit is part of the Lighthouse Tenement and bears
significant geological similarities to the nearby Mt Wright gold mine (45km to
the northeast), where 1.5 million ounces of gold have been mined. More than
14,000 m have been drilled within the Lighthouse tenement.
Drilling to date at the Company's copper projects, Copperhead and Copper Dome
(35 km and 85 km southwest of the town of Proserpine respectively), are
indicative of large-scale porphyry targets. Both projects have been drilled by
previous explorers but remain under-explored, leading the Board to believe
that they demonstrate significant exploration upside potential.
Rockfire Resources has adopted a strategy of growth based on advancing
exploration across its existing portfolio of projects, as well as the
continual assessment of opportunities to acquire outstanding strategic mineral
projects worldwide.
The Company is led by a highly skilled management team, with a proven track
record in exploring and discovering projects.
Background to Copperhead
The Copperhead Project is located ~35 km southwest of the town of Proserpine
and is held by BGM Investments Pty Ltd, a 100% owned subsidiary of Rockfire
Resources plc.
The Copperhead drilling database consists of 3,144.8 m of diamond drilling in
10 holes. The surface geochemistry was utilised to provide approximate
surficial extents to the mineralisation.
· A mineral Resource has been completed for the Copperhead Deposit,
totalling 64 Mt @ 0.19 % Cu EQ ( 1 ) for 120,000 t of Cu Eq. in the inferred
category.
Mineral Resource Statement (effective date 14th March 2022)
Cut-off (Grade Cu Eq %) Resource Category Tonnage (Mt) Grade Contained Metal
Cu Eq % Cu % Mo % Ag (g/t) Cu Eq (Kt) Cu (Kt) Mo (Kt) Ag (M oz)
0.13 Inferred 64 0.19 0.12 0.015 0.55 120 80 9.4 1.1
Notes:
1. Mr Edward Fry, MAusIMM (CP) is responsible for this Mineral Resource
statement.
2. Mr Edward Fry is a full-time employee and shareholder of Rockfire
Resources plc.
3. The Mineral Resource is reported using a cut-off grade approximated
for the open pit mining method.
4. Mineral Resources are not Mineral Reserves and do not have
demonstrated economic viability
5. Figures may not compute due to rounding to 2 significant places.
6. The Copper equivalency formula is as follows:
Copper equivalent metal prices as of 17 February 2022
A B C
Grade (ppm) Metal Price (US$) B Unit Factor C Unit
1 Cu 10045 US$/t 1000000 ppm/t
2 Mo 18.92 US$/lb 454 ppm/lb
3 Ag 22.89 US$/oz 31.10348 ppm/t
Copper equivalent formula
Cu Eq = (1A x 1B/1C + 2A x 2B/2C + 3A x 3B/3C) / 1B x 1C
Mineral Resource Sensitivity Analysis (Cut-off grade)
Mineral Resource Statement (effective date 14th March 2022)
Cut-off (Grade Cu Eq %) Resource Category Tonnage (Mt) Grade Contained Metal
Cu Eq % Cu % Mo % Ag (g/t) Cu Eq (Kt) Cu (Kt) Mo (Kt) Ag (M oz)
0.15 Inferred 48 0.21 0.14 0.016 0.59 100 160 7.7 0.9
0.14 Inferred 54 0.2 0.13 0.016 0.57 110 160 8.4 1
0.13 Inferred 64 0.19 0.12 0.015 0.55 120 150 9.4 1.1
0.12 Inferred 70 0.19 0.12 0.014 0.54 130 140 9.9 1.2
0.11 Inferred 80 0.18 0.12 0.014 0.52 140 140 10 1.3
0.1 Inferred 88 0.17 0.11 0.013 0.51 150 130 12 1.4
0.05 Inferred 110 0.15 0.099 0.012 0.47 170 120 13 1.7
0 Inferred 110 0.15 0.097 0.011 0.47 170 110 13 1.7
· The Mineral Resource Estimate follows the 2012 edition of the
Australasian Code for the reporting of Exploration Results, Mineral Resources
and Ore Reserves (JORC Code 2012 Edition)
· The estimation process utilised Inverse Distance Powered
method
· The Mineralised zones were modelled using a soft boundary
determined wireframe in Micromine
· The lithological interpretation consisted of two rock units
(a pre-mineralised igneous suite of gabbros/tonalites) and a post
mineralisation dolerite dyke
· The Reasonable Prospects for Eventual Economic Extraction are
based solely on an open pit scenario utilising the 0.13 % Cu Eq base-cut. The
base-cut was chosen given the high current copper price.
Notes:
1. Mineral Resources do not demonstrate economic viability.
2. Rounding may result in apparent summation differences between
tonnes, grade and contained metal content.
1. JORC Code, 2012 Edition - Table 1 Report: Copperhead Resource Mar 15, 2022
1.1. 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 (e.g. cut channels, random chips, or specific Sampling was completed using Diamond Drilling (DD). A total of 10 drill holes
specialised industry standard measurement tools appropriate to the minerals exist for the project, of which 8 were used in the mineral estimate.
under investigation, such as down hole gamma sondes, or handheld XRF
instruments, etc). These examples should not be taken as limiting the broad DD core was transferred to core trays for logging and sampling. Half core was
meaning of sampling. sampled typically on a 1m basis.
Include reference to measures taken to ensure sample representivity and the Core is aligned and measured by tape, comparing back to down hole core blocks
appropriate calibration of any measurement tools or systems used. consistent with industry practice where observed.
Aspects of the determination of mineralisation that are Material to the Public Diamond drilling sampling was completed by respected companies to an assumed
Report. In cases where 'industry standard' work has been done this would be industry standard,
relatively simple (e.g. 'reverse circulation drilling was used to obtain 1 m
samples from which 3 kg was pulverised to produce a 30 g charge for fire The sample is crushed and pulverised to produce an approximate ~200g pulp sub
assay'). In other cases more explanation may be required, such as where there sample to use in the assay process.
is coarse gold that has inherent sampling problems. Unusual commodities or
mineralisation types (e.g. submarine nodules) may warrant disclosure of
detailed information.
Historical assays fail to denote the assay method used.
Drilling techniques Drill type (e.g. core, reverse circulation, open-hole hammer, rotary air Only diamond drilling was used at the Copperhead Prospect.
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, All diamond drill holes NQ with a HQ collar.
whether core is oriented and if so, by what method, etc).
Historical drill core was unable to be located.
Drill sample recovery Method of recording and assessing core and chip sample recoveries and results Recovery was excellent for both diamond core. The majority of the core
assessed. contains photographic records.
Measures taken to maximise sample recovery and ensure representative nature of For diamond drilling the contractors adjust their rate of drilling and method
the samples. if recovery issues arise. All recovery is recorded by the drillers on core
blocks. This is checked and compared to the measurements of the core by
inter-block run lengths.
Whether a relationship exists between sample recovery and grade and whether There is no known relationship between sample recovery and grade, sample
sample bias may have occurred due to preferential loss/gain of fine/coarse recovery is high
material.
Logging Whether core and chip samples have been geologically and geotechnically logged All diamond core is logged for, lithology, veining, alteration, mineralisation
to a level of detail to support appropriate Mineral Resource estimation, and structure where recorded.
mining studies and metallurgical studies.
Whether logging is qualitative or quantitative in nature. Core (or costean, All logging is quantitative where possible, qualitative elsewhere.
channel, etc) photography.
The total length and percentage of the relevant intersections logged. 100% of the drill core is logged
Sub-sampling techniques and sample preparation If core, whether cut or sawn and whether quarter, half or all core taken. The historical diamond core was half sampled approximately every 30 m. T-tests
indicate that their drill assays are not significantly different from
Rockfire's drill assays. The Rockfire drill sampling was completed by using a
core saw to ½ sample the core, which was ¼ sampled every 30 m for QAQC
purposes.
If non-core, whether riffled, tube sampled, rotary split, etc and whether NA.
sampled wet or dry.
For all sample types, the nature, quality and appropriateness of the sample Sample preparation was not observed but is assumed best industry practice at
preparation technique. that time and deemed adequate.
Quality control procedures adopted for all sub-sampling stages to maximise Field control samples and blanks were utilised were taken for the recent ROCK
representivity of samples. DD sampling every 30m.
It is unknown from literature if historical duplicates were taken. It is
assumed that they were not.
Measures taken to ensure that the sampling is representative of the in situ Field duplicate samples were utilised were taken for the recent ROCK DD
material collected, including for instance results for field duplicate / sampling every 30m.
second-half sampling.
It is unknown from literature if historical duplicates were taken. It is
assumed that they were not.
Whether sample sizes are appropriate to the grain size of the material being Sample sizes are considered appropriate as assumed Industry practice.
sampled.
Quality of assay data and laboratory tests The nature, quality and appropriateness of the assaying and laboratory QAQC analysis for the control samples indicate that the lab was in control for
procedures used and whether the technique is considered partial or total. the analyses. No significant contamination was recorded in the blank samples.
The duplicates show reasonable correlation.
For geophysical tools, spectrometers, handheld XRF instruments, etc, the No geophysical tools were used to determine any element concentrations
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 (e.g. standards, blanks, Certified reference materials (CRMs) were historically not inserted into the
duplicates, external laboratory checks) and whether acceptable levels of sample sequence. The recent ROCK drilling incorporated a standard every 30m.
accuracy (i.e. lack of bias) and precision have been established. Blanks and standards are placed in the analysis runs by the Laboratories under
their own QA/QC programs.
Verification of sampling and assaying The verification of significant intersections by either independent or All significant intersections are verified by internal ROCK geologists during
alternative company personnel. the drill hole validation process.
The use of twinned holes. One ROCK hole twinned a historical diamond drill hole. The holes show relative
similar geology and grade trends.
Documentation of primary data, data entry procedures, data verification, data Geological logging was captured using paper logs and entered later into excel
storage (physical and electronic) protocols. templates. Both a hardcopy and electronic copy of these are stored, as well as
being loaded into the database using manual techniques. The CP has verified
this data on approximately 5 % of the samples. Assay files are received in csv
format for new holes and copied direct into the excel log. The Geologist then
checks the assays against historical logs. A geologist then checks that the
results have been inserted correctly. Hardcopy and electronic copies of these
are stored. No adjustments are made to this assay data.
Visual checks are conducted as part of the validation process of the data in
Micromine software.
Discuss any adjustment to assay data. No adjustments, only the first primary lab assays are used. Where there are
duplicate samples, a simple average of the two samples is used.
Location of data points Accuracy and quality of surveys used to locate drill holes (collar and Handheld GPS and high-resolution drone air photographs were used to locate the
down-hole surveys), trenches, mine workings and other locations used in drill holes.
Mineral Resource estimation.
Reviews of the historical literature highlight with limited downhole surveys
were recorded.
Specification of the grid system used. Holes are based on the Map Grid of Australia 94, zone 55.
Quality and adequacy of topographic control. Topographic control is derived from 3D drone photography.
Data spacing and distribution Data spacing for reporting of Exploration Results. Exploration result data spacing can be highly variable, from 1 m up to 150 m
Whether the data spacing and distribution is sufficient to establish the Drill hole spacing across the prospect is not systematic and is variable in
degree of geological and grade continuity appropriate for the Mineral Resource nature.
and Ore Reserve estimation procedure(s) and classifications applied.
Whether sample compositing has been applied. Over 99% of the sample lengths were 1m, only minimal compositing to the 1m
length occurred.
Orientation of data in relation to geological structure Whether the orientation of sampling achieves unbiased sampling of possible The orientation of the drill holes are oblique to the strike and also in
structures and the extent to which this is known, considering the deposit opposite directions. No significant difference was noted in the differing hole
type. orientations.
If the relationship between the drilling orientation and the orientation of Given the style of mineralisation (close spaced sheet vein broad porphyry) and
key mineralised structures is considered to have introduced a sampling bias, the steepness of the broad mineralised zones no material sampling bias is
this should be assessed and reported if material. considered to have been introduced by the drilling orientation.
Sample security The measures taken to ensure sample security. Samples were managed at site and hand delivered to ALS by ROCK staff. No
record of the historical chain of custody measures were observed in the
historical literature
Audits or reviews The results of any audits or reviews of sampling techniques and data. Review of historical sampling is considered meeting industry practice by
previous operators.
1.2. 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 The Copperhead prospect is situated on EPM 25531, which is 100% owned by BGM
material issues with third parties such as joint ventures, partnerships, Investments Pty Ltd (a wholly owned subsidiary of ROCK). No material third
overriding royalties, native title interests, historical sites, wilderness or party issues exist at Copperhead.
national park and environmental settings.
The security of the tenure held at the time of reporting along with any known EPM 25531is in good standing with the Queensland Government. No impediments
impediments to obtaining a licence to operate in the area. have been identified to date.
Exploration done by other parties Acknowledgment and appraisal of exploration by other parties. Exploration has been completed by other parties including Carpentaria
Exploration pty ltd (exploration arm of MIM). The historical work was
completed using a local grid. All relevant data was recorded in annual
exploration reports. The data has been validated by ROCK staff and is
considered to be of a high quality.
ROCK commenced compilation of all the paper data in 2017 to support the
generation of technical information and the new mineral resource.
The local grid was constrained using GPS located historical and current
topographical features.
Geology Deposit type, geological setting and style of mineralisation. The deposit is considered as being a deep seated sheeted vein Cu-Mo-Ag
porphyry.
Drill hole Information A summary of all information material to the understanding of the exploration CH DH MASTER ASSAY
results including a tabulation of the following information for all Material
drill holes: CH DH MASTER COLLAR
o easting and northing of the drill hole collar CH DH MASTER GEOLOGY
o elevation or RL (Reduced Level - elevation above sea level in metres) of CH DH MASTER MSUS
the drill hole collar
CH DH MASTER SG
o dip and azimuth of the hole
CH DH MASTER SURVEY
o down hole length and interception depth
Please contact the company if you require more detailed information.
o hole length.
If the exclusion of this information is justified on the basis that the Not Applicable
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, maximum All diamond core results have been reported using the from-to weighting method
and/or minimum grade truncations (e.g. cutting of high grades) and cut-off in the Micromine software. The cut of grade for the mineral resource estimate
grades are usually Material and should be stated. is discussed below.
Where aggregate intercepts incorporate short lengths of high grade results and Given the mineralisation style, sampling a 1m intervals was considered
longer lengths of low grade results, the procedure used for such aggregation representative and appropriate.
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 N/A
clearly stated.
Relationship between mineralisation widths and intercept lengths These relationships are particularly important in the reporting of Exploration Downhole lengths have been reported
Results.
If the geometry of the mineralisation with respect to the drill hole angle is The drilling intersects the known mineralisation at high angle
known, its nature should be reported.
If it is not known and only the down hole lengths are reported, there should To be noted as required and all lengths are considered as downhole lengths.
be a clear statement to this effect (e.g. 'down hole length, true width not
known').
Diagrams Appropriate maps and sections (with scales) and tabulations of intercepts Diagrams have been attached for geometry in plan view
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.
Balanced reporting Where comprehensive reporting of all Exploration Results is not practicable, Mineralisation for low grades and high grades are highlighted
representative reporting of both low and high grades and/or widths should be
practiced to avoid misleading reporting of Exploration Results.
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 No additional relevant information exists at this time.
treatment; metallurgical test results; bulk density, groundwater, geotechnical
and rock characteristics; potential deleterious or contaminating substances.
Further work The nature and scale of planned further work (e.g. tests for lateral Further work is planned in 2022 to enhance understanding of the deposit.
extensions or depth extensions or large-scale step-out drilling).
Diagrams clearly highlighting the areas of possible extensions, including the See 3D section in Appendix 1
main geological interpretations and future drilling areas, provided this
information is not commercially sensitive.
1.3. Section 3 Estimation and Reporting of Mineral Resources
(Criteria listed in section 1, and where relevant in section 2, also apply to this section.)
Criteria JORC Code explanation Commentary
Database integrity Measures taken to ensure that data has not been corrupted by, for example, All data is stored in a digital database with logging and assays being
transcription or keying errors, between its initial collection and its use for compared to original logs and assay sheets. Validation is also done against
Mineral Resource estimation purposes. old paper plans. Downhole validation checks are made when loading into
Micromine software.
Data validation procedures used. All data is manually validated and only approved data is used for the resource
estimation.
Site visits Comment on any site visits undertaken by the Competent Person and the outcome Site visits were undertaken by the Competent Person.
of those visits.
If no site visits have been undertaken indicate why this is the case. NA
Geological interpretation Confidence in (or conversely, the uncertainty of) the geological The geological interpretation is very simple and has high confidence.
interpretation of the mineral deposit.
Nature of the data used and of any assumptions made. The interpretation is primarily supported by Geological logging of drill core
and geologic mapping.
The effect, if any, of alternative interpretations on Mineral Resource No alternative interpretations have been completed to date.
estimation.
The use of geology in guiding and controlling Mineral Resource estimation. The geology (sulphide/gossanous rich fault zones) and alteration logging was
used in determining the unmineralised domain which overprints the
mineralisation. The mineralised zone is modelled using a soft boundary and is
independent of the host geology.
The factors affecting continuity both of grade and geology. The deposit is a sheeted vein porphyry system. Faults, fractures and veins are
the main drivers. No material relationship
Dimensions The extent and variability of the Mineral Resource expressed as length (along Mineralisation has been identified over a strike length approximately of 700m
strike or otherwise), plan width, and depth below surface to the upper and and over a down hole depth of approximately 400m to date. Due to the lack of
lower limits of the Mineral Resource. outcrop, it is unclear how far or how many additional mineralised zones exist.
Estimation and modelling techniques The nature and appropriateness of the estimation technique(s) applied and key Drill holes were composited into 1.0m intervals down hole within each
assumptions, including treatment of extreme grade values, domaining, interpreted domain. The average grade and total length of the composite data
interpolation parameters and maximum distance of extrapolation from data was compared against the average grade and total length of the uncomposited
points. If a computer assisted estimation method was chosen include a data to check the compositing process. The distribution of composite lengths
description of computer software and parameters used. were checked to ensure that the majority of the composites were close to the
targeted length.
Anisotropic inverse distance power (IDW to the power of 2) was the estimating
method used.
Search distances used for estimation based on the drill spacing and target
definition levels.
Grades were estimated into 10x10x10m panels.
The availability of check estimates, previous estimates and/or mine production No previous JORC Mineral Resource estimate for Copperhead exists. A check
records and whether the Mineral Resource estimate takes appropriate account of estimate against the wireframe grade tonnage report was completed. No material
such data. unexplainable difference was observed.
The assumptions made regarding recovery of by-products. 100% recovery of by-products has been assumed
Estimation of deleterious elements or other non-grade variables of economic No deleterious elements are estimated in the model
significance (e.g. sulphur for acid mine drainage characterisation).
In the case of block model interpolation, the block size in relation to the 10x10x10m panels.
average sample spacing and the search employed.
Search ellipsoids are (Axis 1) 130 m (Axis 2) 130 m by 5 m (Axis 3)
Any assumptions behind modelling of selective mining units. NA
Any assumptions about correlation between variables. Visualisation in Micromine of block grade versus drill hole grade comparisons.
Description of how the geological interpretation was used to control the Mineralised zones were constrained according to grade and structural features.
resource estimates. There is a post mineralisation dolerite dyke which was modelled and this zone
was excised from the mineralisation model
Discussion of basis for using or not using grade cutting or capping. Top-cuts were applied to the sample data based on Log Probability plot
statistical analysis of the data total domain
The process of validation, the checking process used, the comparison of model The estimated grades were assessed against sample grades and against the
data to drill hole data, and use of reconciliation data if available. wireframe grade tonnage report
Moisture Whether the tonnages are estimated on a dry basis or with natural moisture, Tonnes were assumed to be dry in situ
and the method of determination of the moisture content.
Cut-off parameters The basis of the adopted cut-off grade(s) or quality parameters applied. Cut-off grades for reporting the base resource were developed using a Copper
Price of $USD 10,100.
A cut-off grade of 1300 Cu Eq was adopted as the base for reporting
Mining factors or assumptions Assumptions made regarding possible mining methods, minimum mining dimensions No assumptions made for mining apart from a minimum 1 metre composite at grade
and internal (or, if applicable, external) mining dilution. It is always and supporting geology.
necessary as part of the process of determining reasonable prospects for
eventual economic extraction to consider potential mining methods, but the
assumptions made regarding mining methods and parameters when estimating
Mineral Resources may not always be rigorous. Where this is the case, this
should be reported with an explanation of the basis of the mining assumptions
made.
Metallurgical factors or assumptions The basis for assumptions or predictions regarding metallurgical amenability. No metallurgical test work historical or current exists for the prospect and
It is always necessary as part of the process of determining reasonable considered contained gold metal.
prospects for eventual economic extraction to consider potential metallurgical
methods, but the assumptions regarding metallurgical treatment processes and
parameters made when reporting Mineral Resources may not always be rigorous.
Where this is the case, this should be reported with an explanation of the
basis of the metallurgical assumptions made.
Environmental factors or assumptions Assumptions made regarding possible waste and process residue disposal Given the early-stage nature of the prospect, no environmental factors or
options. It is always necessary as part of the process of determining concerns are observed at current.
reasonable prospects for eventual economic extraction to consider the
potential environmental impacts of the mining and processing operation. While
at this stage the determination of potential environmental impacts,
particularly for a greenfields project, may not always be well advanced, the
status of early consideration of these potential environmental impacts should
be reported. Where these aspects have not been considered this should be
reported with an explanation of the environmental assumptions made.
Bulk density Whether assumed or determined. If assumed, the basis for the assumptions. If Bulk density measurments were recorded for all ROCK drill holes. The method
determined, the method used, whether wet or dry, the frequency of the used for determining the SG was the weight in air vs the weight in water
measurements, the nature, size and representativeness of the samples. method.
The bulk density for bulk material must have been measured by methods that No/minimal voids are encountered or anticipated.
adequately account for void spaces (vugs, porosity, etc), moisture and
differences between rock and alteration zones within the deposit.
Discuss assumptions for bulk density estimates used in the evaluation process No materially different zones were encountered.
of the different materials.
Classification The basis for the classification of the Mineral Resources into varying The entirety of the resource is classified as inferred. This is because there
confidence categories. is sufficient geochemical knowledge at surface to delineate the deposit's
surface extent. There is sufficient drilling at depth to characterise the
mineralisation beneath this footprint to infer that mineralisation continues.
There is insufficient data to predict which reasonable confidence what that
grade. As such, none of the resource was included in the indicated category.
Whether appropriate account has been taken of all relevant factors (i.e.. Yes, the deposit is a bulk tonnage Cu-Mo-Ag deposit and as such sufficient
relative confidence in tonnage/grade estimations, reliability of input data, account has been taken for all relevant factors.
confidence in continuity of geology and metal values, quality, quantity and
distribution of the data).
Whether the result appropriately reflects the Competent Person's view of the This mineral resource estimate is considered representative as an early-stage
deposit. prospect.
Audits or reviews The results of any audits or reviews of Mineral Resource estimates. The resource model has not had external reviews.
Discussion of relative accuracy/ confidence Where appropriate a statement of the relative accuracy and confidence level in Given the deposit is a bulk tonnage Cu-Mo-Ag sheeted porphyry system, only
the Mineral Resource estimate using an approach or procedure deemed minimal variation is predicted which the currently defined zones. The
appropriate by the Competent Person. For example, the application of descriptive statistics indicate that there is a low <1.2 CoV for Cu, which
statistical or geostatistical procedures to quantify the relative accuracy of indicates drilling into a system with minimal variation, i.e., only one
the resource within stated confidence limits, or, if such an approach is not mineralising event. The structurally controlled nature of the sheeted veins
deemed appropriate, a qualitative discussion of the factors that could affect indicates that variation within the currently drill sections of the deposit
the relative accuracy and confidence of the estimate. will probably not be large. The surface extent is controlled by the surface
geochemistry and the drilling provides confidence level to a standard of an
inferred resource.
The statement should specify whether it relates to global or local estimates, The estimate is considered to be a global estimate.
and, if local, state the relevant tonnages, which should be relevant to
technical and economic evaluation. Documentation should include assumptions
made and the procedures used.
These statements of relative accuracy and confidence of the estimate should be No production data is available
compared with production data, where available.
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