Further Targets Confirmed at Commonwealth Project
Released
Released
Announcement PDF
ASX ANNOUNCEMENT
Date: 23rd June 2020
Number: 682/230620
FURTHER SIGNIFICANT TARGETS CONFIRMED AT THE
COMMONWEALTH PROJECT
NEAR THE BODA DISCOVERY IN NEW SOUTH WALES
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Rock chip assays return up to 9.5 g/t gold, 215 g/t silver (7 ounces) and 745 ppm bismuth
from the Greenobbys prospect and up to 0.1% copper, 2 g/t silver and 40 ppm bismuth
from Boda South.
Pathfinder metal and alteration minerals indicate there are two different styles of
mineralisation: epithermal gold-silver at Greenobbys and porphyry copper-gold at Boda
South along trend from Alkane Resources Limited’s Boda discovery.
Greenobbys covers the western margin of a Carboniferous granite and the high grade
gold and silver occurs in quartz-feldspar veins and is associated with an unusually large
array of pathfinder metals.
This is a new style of mineralisation for this area and is suggestive of a telescoped
epithermal gold-silver system driven by cooling of the host granite. The margin of the
granite extends over many strike kilometres on Impact’s ground and has not been
previously explored.
At Boda South, which covers the southern extension of the Boda Intrusive Complex, host
to the Boda deposit, copper-bearing, Ordovician-aged and epidote altered shoshonite
volcanics indicate the prospect may lie in the outer distal zone of a major porphyry
copper gold deposit such Cadia-Ridgeway.
A detailed airborne magnetic and radiometric survey has recently been completed over
all five of Impact’s priority prospects and a soil geochemistry survey is in progress at the
Apsley Prospect. This data will be used to help define follow up work programmes
including drilling.
The significant exploration potential for large intrusion-related gold and copper-gold deposits at
Impact Minerals Limited’s (ASX:IPT) 100% owned Commonwealth project in the Lachlan
copper-gold province in New South Wales has further been confirmed and enhanced by new assay
results from 27 rock chip samples at two prospects (Figure 1 and Table 1).
The two prospects, Greenobbys and Boda South, were identified as part of a group of five
priority areas for follow up exploration by Impact prompted by the recent major porphyry coppergold discovery at Boda-Kaiser by Alkane Resources Limited (ASX:ALK Releases 9th September
2019 and 19th May 2020).
Figure 1. Location of Impact’s Commonwealth, Pine Hill and Day Dawn Projects covering about
900 sq. km of the Lachlan Fold Belt of NSW, home to many significant gold and copper mines.
Two of the other priority areas, Apsley and Spicers Creek have significant porphyry copper gold
potential because they each have a number of characteristics commonly seen around giant alkaline
porphyry copper-gold systems globally such as Cadia-Ridgeway and Boda (Figure 2 and IPT:ASX
Releases 22nd November 2019 and 23rd April 2020).
These are:
1. Copper-bearing shoshonite host rocks of Ordovician age (a specific high potassium alkaline
rock);
2. metal assemblages and alteration minerals characteristic of the outer to inner zones of the
porphyry systems; and
3. an association with magnetic anomalies that may represent “skarn’ alteration directly
associated with copper-gold mineralisation as also seen at Boda.
Impact’s fifth priority area Gladstone is currently being evaluated and awaiting final airborne
magnetic and radiometric data (Figure 2).
Figure 2. Priority prospects for follow up work and geology at the Commonwealth Project. Note the
location of the Boda-Kaiser prospect (Alkane Resources Limited) and the Lady Ilse prospect
(Magmatic Resources Limited) where drilling is in progress (ASX:MAG ASX Release 18th June
2020).
GREENOBBYS
The Greenobbys prospect lies a few kilometres east of Boda South and covers the variably magnetic
western margin of the very potassium-rich Wuuluman Granite which is of Carboniferous age (Figures
2 and 3). These rocks are much younger than the Boda Intrusive Complex and are in a different
geological setting.
Figure 3. Airborne magnetic image of the Boda South and Greenobbys Prospects with gold assay
results and interpreted alteration zones. Warmer colours on the image represent stronger magnetic
responses.
Key features identified at Greenobbys include:
1. Several north west trending zones of rubbly outcrop of quartz and potassium feldspar
(“K-feldspar”) veins that each extend over at least 500 metres of trend. These zones are parallel
to faults noted on the government Geological Survey maps and also the controlling faults at the
rich Bodangora Mine located 4 km to the west and which produced about 250,000 ounces of
gold at greater than 20 g/t in similar quartz veins (owned by Magmatic Resources Limited;
Figure 2).
2. The veins show a gradation from coarse K-feldspar with lesser quartz (pegmatite), to
K-feldspar and grey quartz in equal proportions to creamy white quartz with little or no
K-feldspar (Figure 4).
3. The quartz dominant veins are vuggy and contain boxwork gossan formed by the weathering of
sulphides including pyrite (Figure 4). There are a number of shallow pits along the vein
system.
1 cm
1 cm
1 cm
Figure 4. Gradation of veins from K-feldspar dominant (left photo) to quartz-dominant (right photo)
with increasing boxwork gossan (dark brown colour) from weathered sulphides.
These veins contain up to 9.5g/t gold (six samples with more than 1 g/t gold) and 215 g/t silver (four
samples with more than 1 ounce per tonne) (Figure 3, Table 1). In addition, the veins contain a
remarkable array of pathfinder metals that are anomalous on a regional scale compared to Impact’s
other prospects in particular bismuth (up to 754 ppm), molybdenum (up to 519 ppm) and tellurium (up
to 40 ppm).
Other pathfinder metals present include selenium-thallium-antimony-arsenic-lead-barium and tungsten
as well as the rare metals indium and rhenium. In addition, preliminary interpretation suggests the
metals are associated with sericite-adularia alteration.
All of these features are interpreted to indicate the veins are related to fluids released from a potassium
rich granite, possibly the host Wuuluman Granite, and which may represent a “telescoped” epithermal
system covering at least several hundred square metres. The veins are open along trend and at depth as
there is no recorded drilling in the area.
Telescoping refers to the significant overlap between proximal and distal metal and mineral
assemblages and suggests the possible rapid collapse of the parent hydrothermal system. This is
encouraging for the discovery of bonanza gold-silver veins.
The scale and size of the vein and alteration system is very encouraging and further field checking and
sampling is warranted.
BODA SOUTH PROSPECT
The Boda South prospect, which is undrilled, covers the faulted southern contact of the Boda Intrusive
Complex (BIC), host to the Boda-Kaiser mineralisation and which is Ordovician in age (Figures 2 and
3). As demonstrated at Apsley and Spicers Creek, Boda South also contains the fundamental
characteristics required to potentially host a significant porphyry copper-gold deposit:
1. Copper-bearing Ordovician shoshonites with weak to moderate copper assays of up to 0.1%
with copper increasing as the rocks become more potassium rich (shoshonitic - Figure 5).
2. Metal assemblages of up to 40 ppm bismuth and 21 ppm tellurium as well as moderate epidotechlorite alteration indicate the area may lie in the upper phyllic to outer (propylitic) zone of a
porphyry copper-gold system. Typical values of both these pathfinders documented above
known deposits are in the order of about 1 to 5 ppm.
3. An association with two sub-parallel magnetic anomalies within the BIC as evident in regional
magnetic data (Figure 3). This is a similar position to the Boda deposit, located about 3,000
metres along trend to the north, where the high grade copper-gold mineralisation discovered by
Alkane also occurs between two magnetic units of the BIC (Figure 2 and ASX:ALK Release
23rd March 2020).
Given the prospective nature of the BIC, modelling of magnetic data is required to determine the depth
to the intrusive complex at Boda South. This work will be done when data from the recently
completed magnetic survey is received and will help guide follow up work programmes.
Figure 5. Major element ratio plot for Boda South (triangles) together with Apsley (squares) and
Spicers Creek (circles) with copper results coloured by grade. An igneous differentiation trend towards
copper-bearing high potassium-shoshonite rocks is evident; this is common to major porphyry copper
deposits in the Lachlan Fold Belt (Apsley and Spicers Creek results in ASX:IPT Release 23rd April
2020).
NEXT STEPS
These results, together with those from Apsley and Spicers Creek strongly support the potential for the
Commonwealth Project to host not only significant porphyry copper-gold deposits but also intrusionrelated epithermal gold-silver deposits. Further work is now required to refine and rank these target
areas for drilling.
At present the Apsley target is ranked as the most prospective and a detailed soil geochemistry survey
is now in progress there. Results are expected by early August.
In addition, a detailed airborne magnetic and radiometric survey covering Impact’s five priority areas
has recently been completed and final data is anticipated within two weeks.
All of this new data will be interpreted and synthesised to help define follow up work programmes
which will include drilling later in 2020.
Impact Minerals Limited Managing Director Dr Mike Jones said:
“Our reconnaissance rock chip assays across four of our priority targets have exceeded our
expectations as they have all returned encouraging results that require follow up exploration. This has
further confirmed and enhanced our belief that our extensive ground holdings in the prolific Lachlan
Fold Belt have the potential to host not only a major porphyry copper-gold deposit, but also other
possible styles of intrusion-related mineral deposits such as the newly recognised epithermal goldsilver mineralisation at Greenobbys. Incredibly none of these prospects has been drilled and we will
be doing the necessary work to get them to drill ready status as rapidly as we can”.
COMPLIANCE STATEMENT
This report contains new Exploration Results for 27 rock chip samples collected by Impact Minerals
Limited.
Dr Michael G Jones
Managing Director
COMPETENT PERSONS STATEMENT
The review of exploration activities and results contained in this report is based on information compiled by Dr Mike Jones, a
Member of the Australian Institute of Geoscientists. He is a director of the company and works for Impact Minerals Limited.
He has sufficient experience which is relevant to the style of mineralisation and types of deposits under consideration and to
the activity which he is undertaking 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 (the JORC Code). Mike Jones has
consented to the inclusion in the report of the matters based on his information in the form and context in which it appears.
Table 1. New Rock Chip Assays
Sample
ID
Prospect
Easting
Northing
Au_g/t
Ag_g/t
Bi_pp
m
Cu_pp
m
Mo_pp
m
Te_pp
m
W_pp
m
ln_pp
m
BD19
Boda South
690652
6408121
<0.005
0.03
0.02
6.3
2.59
<0.05
0.1
0.003
BD20
Boda South
690652
6408126
0.0070
0.1
0.01
150.5
1.06
0.16
0.4
0.052
BD21
Boda South
690649
6408125
0.0080
0.21
0.17
298
1.1
0.12
0.8
0.090
BD22
Boda South
690458
6408088
<0.005
0.02
0.03
89
0.81
<0.05
0.5
0.057
BD23
Boda South
690473
6408093
<0.005
0.1
39.9
38.8
1.73
21.3
0.7
0.003
BD24
Boda South
690498
6408090
<0.005
0.04
0.2
98.6
0.84
0.12
0.5
0.037
BD25
Boda South
690134
6408047
<0.005
<0.01
0.05
16.5
0.44
<0.05
0.5
0.047
BD26
Boda South
690133
6408046
0.0550
0.11
0.02
333
0.72
<0.05
0.5
0.050
BD27
Boda South
689962
6407871
<0.005
0.0
0.1
89
0.4
0.06
0.4
0.054
BD28
Boda South
689950
6407855
0.0130
2.1
14.8
1005
1.4
<0.05
3.6
0.055
BD29
Boda South
689957
6407788
<0.005
0.0
0.0
67
0.6
<0.05
0.7
0.037
BD30
Boda South
689903
6407859
<0.005
0.0
0.2
62
0.7
0.13
0.5
0.055
GB01
Greenobbys
691954
6406349
0.9190
9.7
328.0
47
143.5
4.41
1.6
0.042
GB02
Greenobbys
691979
6406256
0.0050
0.3
1.9
615
5.6
<0.05
1.3
0.050
GB03
Greenobbys
692078
6406260
1.2150
33.2
467.0
486
217.0
15.65
8.4
0.326
GB04
Greenobbys
692087
6406362
1.6800
157.0
754.0
209
519.0
15.20
1.0
0.186
GB05
Greenobbys
692133
6406216
0.0130
0.7
4.0
11
4.1
0.18
0.7
0.003
GB06
Greenobbys
692231
6406538
<0.005
0.8
2.3
15
2.2
0.24
3.4
0.003
GB07
Greenobbys
692291
6406645
0.1090
8.3
47.3
30
13.5
1.98
2.2
0.011
GB08
Greenobbys
692294
6406612
0.0080
0.9
4.1
13
4.4
0.13
1.7
0.007
11151
Greenobbys
692143
6406274
0.1590
3.9
26.4
54
21.2
2.31
0.6
0.027
11152
Greenobbys
692097
6406260
9.5100
215.0
166.5
444
216.0
40.70
3.3
0.693
11153
Greenobbys
691979
6406253
1.1950
14.1
31.7
511
283.0
1.64
20.2
0.216
11154
Greenobbys
691969
6406246
0.1190
5.6
13.0
124
192.5
2.34
5.5
0.157
11155
Greenobbys
691859
6406256
0.2260
17.9
47.6
68
158.0
7.17
1.2
0.016
11156
Greenobbys
691815
6406264
1.2550
13.3
45.0
105
14.0
1.82
43.2
0.116
11157
Greenobbys
691789
6406271
1.9000
32.7
133.0
181
241.0
9.29
47.4
0.126
Colours represent increasing grades from white lowest through yellow, orange and purple highest
APPENDIX 1 - SECTION 1 SAMPLING TECHNIQUES AND DATA
Criteria
JORC Code explanation
Sampling techniques
Nature and quality of sampling (e.g. 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
Drilling techniques
Drill sample recovery
Logging
Commentary
Rock Chip Samples
Rock chip and grab samples were taken from numerous locations throughout the prospect areas.
Rock Chip Samples
The purpose of the rock chip samples was to establish the tenor of any mineralisation visible in outcrop. Therefore, the samples are
biased towards mineralised samples. This is appropriate for this type of work.
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 (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 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 (e.g. submarine nodules) may warrant
disclosure of detailed information
Rock Chip Samples
Samples weighing up to several kilograms were taken.
Drill type (e.g. core, reverse circulation, 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).
N/A
Method of recording and assessing core and chip sample recoveries
and results assessed
N/A
Measures taken to maximise sample recovery and ensure
representative nature of the samples
N/A
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.
N/A
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.
N/A
N/A
.
Criteria
Sub-sampling
techniques and
sample preparation
JORC Code explanation
The total length and percentage of the relevant intersections
logged
N/A
If core, whether cut or sawn and whether quarter, half or all core
taken.
N/A
If non-core, whether riffled, tube sampled, rotary split, etc and
whether sampled wet or dry.
N/A.
For all sample types, the nature, quality and appropriateness of the
sample preparation technique.
N/A
Quality control procedures adopted for all sub-sampling stages to
maximise representivity of samples.
Quality of assay data
and laboratory tests
Verification of
sampling and assaying
Commentary
Laboratory QC procedures for rock sample assays involve the use of internal certified reference material as assay standards, along
with blanks and duplicates.
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.
Not appropriate for this stage of exploration.
Whether sample sizes are appropriate to the grain size of the
material being sampled.
The size of samples for the rock chips is appropriate for this stage of exploration.
The nature, quality and appropriateness of the assaying and
laboratory procedures used and whether the technique is
considered partial or total.
Industry standard fire assay technique for samples using lead collection with an Atomic Absorption Spectrometry (AAS) finish was
used for gold (Method AU-AA24) and 48 elements by four acid digest ICP-MS (Method ME-MS61) at ALS in Orange.
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.
N/A
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.
Quality control procedures for assays were followed via internal laboratory protocols. Accuracy and precision are within acceptable
limits.
The verification of significant intersections by either independent or
alternative company personnel.
Significant assays have not been verified by independent or alternative companies. This is not required at this stage of exploration.
The use of twinned holes.
N/A
Documentation of primary data, data entry procedures, data
verification, data storage (physical and electronic) protocols.
Primary assay data has been entered into standard Excel templates for plotting in Mapinfo and Target. All historical data has been
entered digitally by previous explorers and verified internally by Impact.
Discuss any adjustment to assay data.
No significant adjustments have been required.
Criteria
Location of data
points
JORC Code explanation
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.
Commentary
Samples were located with a handheld GPS.
Specification of the grid system used.
The grid system for Commonwealth is MGA_GDA94, Zone 55.
Quality and adequacy of topographic control.
N/A
Data spacing for reporting of Exploration Results.
N/A.
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.
N/A
Whether sample compositing has been applied.
N/A
Whether the orientation of sampling achieves unbiased sampling
of possible structures and the extent to which this is known,
considering the deposit type.
N/A
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.
N/A
Sample security
The measures taken to ensure sample security.
For rock samples, chain of custody is managed by Impact Minerals Ltd. Samples for Commonwealth are delivered by Impact
Minerals Ltd personnel to ALS in Orange, NSW. Whilst in storage, they are kept in a locked yard. Tracking sheets have been set up
to track the progress of batches of samples.
Audits or reviews
The results of any audits or reviews of sampling techniques and
data.
This is not material for these Exploration Results.
Data spacing and
distribution
Orientation of data in
relation to geological
structure
SECTION 2 REPORTING OF EXPLORATION RESULTS
Criteria
Mineral tenement and land
tenure status
Exploration done by other
parties
Geology
Drill hole Information
Data aggregation methods
Relationship between
mineralisation widths and
intercept lengths
JORC Code explanation
Commentary
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 Commonwealth Project currently comprises 3 exploration licences covering 315 km2. The tenements
are held 100% by Endeavour Minerals Pty Ltd, a subsidiary company of Impact Minerals Limited. No
aboriginal sites or places have been declared or recorded in areas where Impact is currently exploring.
There are no national parks over the license area.
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 tenements are in good standing with no known impediments.
Acknowledgment and appraisal of exploration by other parties.
No significant exploration has been recorded by previous explorers. Some rock chip samples have been
taken but no drilling.
Deposit type, geological setting and style of mineralisation.
Exploration is focussed on the discovery of porphyry copper-gold mineralisation and other intrusive-related
gold deposit styles.
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:
•
easting and northing of the drill hole collar
•
elevation or RL (Reduced Level – elevation above sea level in
metres) of the drill hole collar
•
dip and azimuth of the hole
•
down hole length and interception depth
•
hole length.
N/A
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.
N/A
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.
N/A
The assumptions used for any reporting of metal equivalent values should be
clearly stated.
N/A
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’).
N/A
Criteria
Diagrams
Balanced reporting
JORC Code explanation
Commentary
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.
Refer to Figures in body of text.
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.
All assay results have been reported.
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.
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
Assessment of other substantive exploration data is not yet complete however considered immaterial at
this stage.
Follow up work programmes will be subject to interpretation of recent and historic results which is ongoing.
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