Silica Hill and Commonwealth Continue to Expand
Released
Released
Announcement PDF
ASX ANNOUNCEMENT
Date: 22 February 2017
Number: 503/220217
SILICA HILL AND COMMONWEALTH CONTINUE TO EXPAND
New drill assay, Induced Polarisation and soil geochemistry data confirm the significant
exploration potential at Commonwealth-Silica Hill
Drill assays from CMIPT048 return:
126 metres at 0.6 g/t gold and 25 g/t silver from 33 metres (1.0 g/t gold equivalent)
including 3 metres at 4 g/t gold and 377 g/t silver (9.6 g/t gold equivalent); and
8 metres at 1.9 g/t gold and 35 g/t silver (2.4 g/t gold equivalent).
Hole CMIPT049 returns a 70 metre thick zone of modest silver mineralisation interpreted to be at
the top of the mineralised system. Lower gold-rich part interpreted to be fault offset to the west.
Mineralisation still open in all directions.
IP Data identifes new chargeability anomalies extending for at least 500 metres north of area
drilled at Silica Hill and new conductivity anomaly below Main Shaft
Chargeability anomalies coincident with significant untested gold and silver-in-soil anomaly also
covering an area of 1,000 metres by 1,000 metres
Numerous new targets identified and a much larger follow up drill programme than anticipated is
being planned with the aim of commencing as soon as practicable, probably in April.
New drill assay, Induced Polarisation (IP) and soil geochemistry data from the Commonwealth-Silica
Hill area at Impact Minerals Limited’s (ASX:IPT) 100%-owned Commonwealth Project 100km north of
Orange in New South Wales continue to demonstrate the significant exploration potential of these key
prospects (Figure 1).
Assay data from two drill holes at Silica Hill have returned thick widths of up to 126 metres of modest
gold and silver mineralisation and confirm the continuity of the mineralised system for a further 50
metres down dip (Figures 2 and 3).
Together with previous drill results significant mineralisation has now been intersected in six drill holes
so far at Silica Hill, over an area of 200 metres by 100 metres down to a depth of 120 metres below
surface and with an average true thickness of at least between 50 metres and 70 metres. The
mineralisation is open in all directions including up dip (Figures 2 and 3 and see also announcement
dated 5th December 2016).
The new IP and soil geochemistry data show that the area partly drilled by Impact covers only the
southern quarter of a much larger target area of up to one square kilometre containing numerous
undrilled IP and gold- and silver-in soil anomalies. In addition a conductor that may represent massive
sulphides has been identified at depth below the Commonwealth resource at Main Shaft.
26 Richardson Street West Perth Western Australia 6005
Tel +61 (8) 6454 6666 Facsimile +61 (8) 6454 6667
Email info@impactminerals.com.au www.impactminerals.com.au
Figure 1. Silica Hill-Commonwealth area: Geology and exploration results. Drill traces shown for Silica
Hill only to demonstrate the small area only partly tested to date. Note the area of greater than 100
gram.metre intercepts and the large untested coincident gold- and silver-in soil and interpreted IP
chargeability anomaly trends. Note also the significant IP anomaly to the north east along the extension of
the Welcome Jack Trend.
This new data, together with previous targets identified over the past 12 months of intensive work by
Impact, have resulted in the identification of a significant number of follow up drill targets at
Commonwealth. This includes targets at depth and along strike from the Commonwealth deposit (Main
Shaft and Commonwealth South); the area covering nearly one square kilometre north of the drilling at
Silica Hill; and follow up work at Welcome Jack and Walls 1,500 metres east of Silica Hill.
Accordingly a much larger drill programme will be required to properly test the targets than previously
anticipated and this is being designed with the aim of commencing in April.
DRILL ASSAY RESULTS FROM SILICA HILL
Two diamond drill holes were completed in late 2016 and returned the following assay results:
Hole CMIPT048 returned:
126 metres at 0.6 g/t gold and 25 g/t silver (1.0 g/t gold equivalent) from 33 metres
including: 6 metres at 1 g/t gold and 26 g/t silver (1.4 g/t gold equivalent) from 58 metres;
and
11 metres at 1.9 g/t gold and 132 g/t silver (3.9 g/t gold eq) from 79 metres
which includes 3 metres at 4 g/t gold and 377 g/t silver (9.6 g/t gold eq) from 84 metres;
and
8 metres at 1.9 g/t gold and 35 g/t silver (2.4 g/t gold eq) from 132 metres
which includes 2 metres at 3.9 g/t gold and 56 g/t silver (4.7 g/t gold eq) from 137 metres.
Detailed studies on the diamond drill core show that this drill hole may not be optimally oriented to
intersect the very high grade silver and high grade gold veins intersected in Hole CMIPT43 which is
between 20 metres and 50 metres away (Figures 2 and 3).
Figure 2. Silica Hill: Significant drill results showing new results from CMIPT048 and 049. The
mineralisation is open in all directions.
Four drill holes out of the six drilled at Silica Hill have returned gram times metre intercepts of more
than 100 gram metres. These are robust and significant results for potential bulk mining and indicate
potential to significantly increase the resources at the Commonwealth Project, which currently stand at
720,000 tonnes at 2.8 g/t gold, 48 g/t silver, 1.5% zinc and 0.6% lead (see announcement 19 February
2015).
Figure 3. Cross section through Silica Hill showing new results from CMIPT048. High grade veins and
shoots in CMIPT046 may plunge off section to the south.
Hole CMIPT049 returned numerous zones of between 5 g/t and 50 g/t silver in a 70 metre thick zone of
mineralisation with best assays of:
13 metres at 0.1 g/t gold and 49 g/t silver (0.8 g/t gold eq) from 174 metres which includes
2 metres at 115 g/t silver from 178 metres and
1 metre at 0.5 g/t gold and 144 g/t silver (2.6 g/t gold eq) from 184 metres.
The mineralisation in this drill hole is terminated by a fault at 189 metres down hole and detailed studies
suggest that only the upper silver rich part of the mineralised zone has been intersected (see
announcement dated 5th December 2016). It is interpreted that the mineralisation has been offset along
the fault to the west, close to Main Shaft and further drilling is required in this area.
The mineralisation at Silica Hill is still open in all directions and further infill and extensional drilling is
required, in particular down dip and also to the north where new IP anomalies have been identified
(Figures 3 and 4).
IP-RESISTIVITY-CONDUCTIVITY SURVEY
New Induced Polarisation geophysical data has identified three significant target areas that have not
been drilled:
1. numerous chargeability anomalies covering an area of at least 500 metres by 500 metres to the
immediate north of the area drilled at Silica Hill (Figure 1 and 4). Previous work by Impact has
shown a strong correlation between IP chargeability anomalies and sulphide mineralisation. The
size and strength of the new anomalies and their coincidence with strong gold- and silver-in soil
anomalies is very encouraging (Figure 1 and 4); and
2. a conductivity anomaly centred at about 100 metres below the deepest drill hole at the northern
part of the Commonwealth deposit at Main Shaft (Figure 5). This drill hole returned 31 metres
at 0.13% copper and 5 g/t silver from 209 metres down hole including 1 metre at 0.7% copper,
1.1% zinc, 0.4% lead, 31 g/t silver and 0.4 g/t gold from 218 metres.
In support of this anomaly, a down hole electromagnetic survey of Hole 6 has also identified a
moderate conductor in a similar position. This is a priority drill target for a down dip extension
of the Commonwealth resource; and
3. a strong chargeability anomaly east of Silica Hill along the northern extension of the Welcome
Jack Trend (Figure 6). No work has been done in this area.
All of these areas require follow up work including drilling.
Figure 4. Three dimensional view from the south of the new IP data showing the extent of the
chargeability anomalies (red areas win dashed oval) north of Silica Hill (drill traces shown in black) and
also the location of the Commonwealth resource. The survey lines are 100 metres apart.
Figure 5. Three dimensional view looking north showing an image of the IP resistivity data with
conductive zones shown in red and also showing the outline of the Commonwealth resource. Note the
conductor at depth below the resource that is undrilled.
Figure 6. View of the new IP data from the south west showing the strong chargeability anomalies to
the east of Silica Hill and to the north of Welcome Jack. No work has been done here.
The IP method is an electrical geophysical survey technique that can identify disseminated sulphides
which manifest themselves as so called chargeability anomalies. In addition the IP method can also
measure how resistive the sub-surface is. For example, large bodies of silica are generally poor
conductors of electricity and so are said to be resistive. Resistivity and conductivity are related by a
simple mathematical equation and therefore conductivity can also be calculated. Massive sulphide
bodies are commonly, but not always, conductive.
SOIL GEOCHEMISTRY SURVEY
A strong gold- and silver-in-soil anomaly that is up to 1,000 metres by 1,000 metres in dimension has
now been defined north of the area drilled at Main Shaft and Silica Hill (Figure 1).
Only about 10% of this area has been drill tested and the strongest and largest part of the anomaly lies to
the north and north east of the area drilled. This is also coincident with the strongest and largest IP
chargeability anomalies (Figures 1, 4 and 7). These are priority areas for drilling.
New environmental approvals will be required in this area.
Figure 7. Three dimensional view from the south of the southern most IP line and showing the
Commonwealth resource and the drill traces at Silica Hill with an image of silver-in-soil (red areas
greater than 1 g/t silver) to the north of the IP line. There is an extensive undrilled silver-in-soil anomaly
covering many hundreds of square metres.
About the Gold-Silver Mineralisation at Silica Hill
The mineralisation discovered by Impact at Silica Hill comprises disseminated sulphide, veins and semimassive sulphide veins within the Silica Hill rhyolite. The veins commonly contain high to very high grades
of gold and in particular silver. For example, Hole CMIPT046 returned 30 individual assays of varying
widths of between 2 g/t and 24 g/t gold and 12 individual assays with more than 500 g/t silver (Figure 4)
and Hole CMIPT011 returned two veins with 3,146 g/t silver (0.9 metres thick) and 3,600 g/t silver (0.15 m
thick).
Four previous drill holes have returned significant intercepts at Silica Hill.
Drill hole CMIPT046 returned high grade gold and very high grade silver over a 41 metre thick intercept
within a 74 metre thick zone of gold-silver mineralisation (Figures 2 and 3).
Key intercepts include:
74.5 metres at 1.2 g/t gold and 106 g/t silver (2.9 g/t gold equivalent) from 61 metres
including 41.3 metres at 2.0 g/t gold and 176 g/t silver (4.7 g/t gold equivalent) from 61 metres;
which includes 16.3 metres at 3.7 g/t gold and 246 g/t silver (7.6 g/t gold equivalent) from 86 metres.
Gold equivalency calculations are based on the following US dollar prices: Gold $1326/oz; silver and $18.82/oz.
The intercept in CMIPT046 includes numerous high grade gold and silver intercepts from individual veins
and groups of veins (which have been sampled in detail) including:
1 metre at 12.2 g/t gold and 680 g/t silver
including 0.3 metres at 23 g/t gold and 1,110 g/t silver;
1 metre at 5.3 g/t gold and 924 g/t silver;
1.7 metres at 3.8 g/t gold and 1,176 g/t silver; and
0.7 metres at 1.5 g/t gold and 855 g/t silver.
Hole CMIPT011 (Figure 8):
48.6 metres at 0.5 g/t gold and 137 g/t silver (2.5 g/t gold equivalent) from 122 metres.
Including
which includes:
and:
which includes
23 metres at 224 g/t silver (3.6 ounces) and 1.0 g/t gold from 147.7 metres
0.9 metres at 3,146 g/t silver (101 ounces) and 2.4 g/t gold from 148.1 metres;
2.9 metres at 406 g/t silver (13 ounces) and 0.6 g/t gold from 157.6 metres
a 15 cm vein that returned 3,600 g (116 ounces) of silver and 0.4 g/t gold;
and also including: 4 metres at 104 g/t (3.4 ounces) silver and 1.5 g/t gold from 160 metres;
and:
1 metre at 4.7 g/t gold and 23 g/t silver from 169.5 metres.
Figure 8. East-West cross section showing results for Holes CMIPT043 and 011.
Hole CMIPT043, drilled above Hole CMIPT011, (Figures 2 and 8) returned:
68 metres at 0.5 g/t gold and 43 g/t silver (1.3 g/t gold equivalent) from 99 metres;
including the upper silver-rich zone of 37 metres at 0.1 g/t gold and 71 g/t silver (2.3 ounces) and the
lower gold-rich zone of 18 m at 1.7 g/t gold and 24 g/t silver from 149 metres.
Individual results of note in this hole are:
High grade silver intercepts (with gold) in the upper part of the assayed zone:
1 m at 122 g/t (4 ounces) silver and 0.2 g/t gold from 108 metres;
1 m at 146 g/t silver (5 ounces) and 0.1 g/t gold from 118 metres;
2 m at 373 g/t (12 ounces) silver and 0.2 g/t gold from 123 metres including
1 m at 525 g/t (17 ounces) silver and 0.1 g/t gold from 124 metres; and
1 m at 337 g/t (11 ounces) silver and 0.1 g/t gold and from 134 metres.
Significant gold assays in the lower part of zone:
1 m at 2.3 g/t gold and 64 g/t (2 ounces) silver from 153 metres; and
1 m at 6.4 g/t gold and 18 g/t silver (0.5 ounces) from 155 metres.
In addition it is evident that there is a large silver “halo” of up to 10 to 15 g/t silver in the Silica Hill rhyolite
which extends further outwards over many hundreds of square metres (Figures 2, 3 and 8). It is possible
that this may be a “leakage halo” from depth and accordingly the down-dip extension of the mineralisation
in Holes CMIPT011 and CMIPT046 are compelling drill targets.
Connection between mineralisation at Main Shaft and Silica Hill
The style and nature of mineralisation in Hole CMIPT043 is similar to that encountered in the rhyolite unit
within the Commonwealth deposit and further demonstrates that the mineralisation at the two prospects is
part of one larger system. It is possible that the mineralisation at Silica Hill and Main Shaft may be linked at
depth. Areas where the two styles of mineralisation may connect will be priority target areas.
A gold-silver-in-soil anomaly extends in a NE direction from Main Shaft to Silica Hill and widens in that
direction. This anomaly is open to the north and north-east. This is a further indication that the two areas
may be linked and further drilling at depth is required.
Very high grade silver values of almost 1 kg/tonne over 1 metre were returned in the 2016 drill programme
from Hole CMIPT031 at Main Shaft in a 7 metre thick zone of massive sulphide mineralisation that
returned:
7 metres at 6.3 g/t gold, 496 g/t silver (15.9 ounces), 7.2% zinc, 2.9% lead and 0.2% copper
(17.7 g/t gold equivalent) from 91 metres
including 3 metres at 10.6 g/t gold, 571 g/t silver (18.4 ounces), 7.8% zinc, 2.1% lead and
0.2% copper (23.0 g/t gold equivalent) from 92 metres and
also including 1 metre at 2.5 g/t gold, 979 g/t silver (31.5 ounces), 8.3% zinc, 4.4% lead and
0.1% copper (21.4 g/t gold equivalent) from 95 metres
This intercept is open down dip, beneath the silver-rich intercepts at Silica Hill (Figure 1).
Dr Michael G Jones
Managing Director
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). Dr 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.
Impact Minerals confirms that it is not aware of any new information or data that materially affects the information included in the
previous market announcements referred to and in the case of mineral resource estimates, that all material assumptions and technical
parameters underpinning the estimates continue to apply and have not materially changed.
APPENDIX 1 - SECTION 1 SAMPLING TECHNIQUES AND DATA
Criteria
JORC Code explanation
Commentary
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.
Rock chip samples
Random grab samples were taken at surface which represented favourable geology and alteration to known mineralisation in the
region. Samples are variably weathered.
Soil Samples
About 250g of soil was taken from 15-20cm below surface and sieved to - 2mm size. Samples put in plastic snap seal bags.
Samples were subsequently sieved to -250 micron at SGS Laboratories for assay by aqua regia digest.
RC Drilling
Reverse Circulation (RC) percussion drilling was used to produce a 1m bulk sample (~25kg) which was collected in plastic bags and
representative 1m split samples (12.5%, or nominally 3kg) were collected using a riffle splitter and placed in a calico bag. The
cyclone was cleaned out with compressed air at the end of each hole and periodically during the drilling. Holes were drilled to
optimally intercept interpreted mineralised zones.
Diamond Drilling
Diamond drilling was used to produce drill core either with a diameter of 63.5 mm (HQ) or 47.6 mm (NQ).
Include reference to measures taken to ensure sample
representivity and the appropriate calibration of any
measurement tools or systems used
Rock chip samples
Representative samples at each sample site weigh between 0.8 and 1.2 kg. Sample sites were chosen due to historic rock and soil
assay results and the geophysical surveys conducted on the Commonwealth Project. Historic rock sample methods are unknown
but are considered immaterial.
Soil Samples and Drill Samples
Sample representivity was ensured by a combination of Company Procedures regarding quality control (QC) and quality assurance
/ testing (QA).
Examples of QC include (but are not limited to), daily workplace and equipment inspections, as well as drilling and sampling
procedures.
Examples of QA include (but are not limited to) collection of “field duplicates”, the use of certified standards and blank samples
approximately every 50 samples
Sampling techniques
Criteria
Drilling techniques
Drill sample recovery
JORC Code explanation
Commentary
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
Rock samples were sent to SGS Perth where they were crushed, dried and pulverised (total prep) to produce a 25-30 g subsamples for analysis initially by Aqua Regia digest with ICP-MS finish for base metals then by four acid digest with an ICP/AES
finish for ore grade base metal samples and lead collection fire assay with AAS finish for gold.
Soil Samples
Soil samples were sent to ACME Laboratories in Vancouver for analysis by aqua regia digest or to SGS Laboratories in Perth for
analysis by the MMI digest.
RC and diamond drill samples
RC samples and cut samples of core were submitted to ALS in Orange, NSW. Laboratory sample preparation involved: sample
crushed to 70% less than 2mm, riffle/rotary split off 1 kg, pulverise split to >85% passing 75 microns.
RC samples analysed by MEICP41 or MEOG46 for ore grade samples, aqua region digest with ICP OES analysis and AA24 fire assay
with AAS finish.
Historical diamond and RC samples were sent to Fox Anamet, Brookvale NSW where gold was determined by fire assay, base
metals by DCP and AAS methods.
Weathered samples contained gossanous sulphide material and fresh samples containing visible pyrite, galena, sphalerite and
chalcopyrite.
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, facesampling bit or other type, whether core is oriented and if so, by
what method, etc).
Diamond drilling accounts for about 50 % of the drilling and comprises NQ (47.6 mm diameter) and HQ (63.5 mm diameter) sized
core. Impact diamond core is triple tube and is oriented. Historical diamond core was not oriented.
RC drilling accounts for about 50% of the drilling and comprises 4 inch hammer.
Method of recording and assessing core and chip sample
recoveries and results assessed
Diamond core recoveries for all holes are logged and recorded. Recoveries are estimated to be approximately >97% for the
Commonwealth Project. No significant core loss or sample recovery problems are observed in the drill core or historic reports. RC
samples were visually checked for recovery, moisture and contamination.
Measures taken to maximise sample recovery and ensure
representative nature of the samples
Diamond core is reconstructed into continuous runs on an angle iron cradle for orientation marking. Depths are checked against
the depth given on the core blocks and rod counts are routinely carried out by the driller.
The RC samples are collected by plastic bag directly from the rig-mounted cyclone and laid directly on the ground in rows of 10.
The drill cyclone and sample buckets are cleaned between rod-changes and after each hole to minimise down-hole and/or cross
contamination.
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.
No sample bias has been established.
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.
Geological logging of samples followed company and industry common practice. Qualitative logging of samples included (but not
limited to); lithology, mineralogy, alteration, veining and weathering. Diamond core logging included additional fields such as
structure and geotechnical parameters.
Magnetic Susceptibility measurements were taken for each 1m RC sample and each 1m diamond core interval.
For diamond core, information on structure type, dip, dip direction, texture, shape and fill material has been recorded in the logs.
RQD data has been recorded on selected diamond holes. Handheld XRF analysis was completed at 50 cm and 1 m intervals on
diamond core and for every metre for RC samples.
Logging
Criteria
Sub-sampling
techniques and
sample preparation
Quality of assay data
and laboratory tests
Verification of
sampling and assaying
JORC Code explanation
Commentary
Whether logging is qualitative or quantitative in nature. Core (or
costean, channel, etc) photography.
All logging is quantitative, based on visual field estimates. Systematic photography of the diamond core in the wet and dry form
was completed.
Chip trays with representative 1m RC samples were collected and photographed then stored for future reference.
The total length and percentage of the relevant intersections
logged
All diamond drill holes were logged in full.
All RC chips samples were geologically logged by Impact’s on-site geologist on a 1m basis, with digital capture in the field.
Detailed diamond core logging, with digital capture was conducted for 100% of the core by Impact’s on-site geologist.
If core, whether cut or sawn and whether quarter, half or all core
taken.
All core samples were sampled by half core. Selected intervals of quarter core will be selected for check assays if required.
If non-core, whether riffled, tube sampled, rotary split, etc and
whether sampled wet or dry.
RC samples were split using a riffle splitter.
For all sample types, the nature, quality and appropriateness of
the sample preparation technique.
Company procedures were followed to ensure sub-sampling adequacy and consistency. These included (but were not limited to),
daily work place inspections of sampling equipment and practices, as well as sub-sample duplicates (“field duplicates”).
Quality control procedures adopted for all sub-sampling stages to
maximise representivity of samples.
Laboratory QC procedures for rock sample assays involve the use of internal certified reference material as assay standards, along
with blanks, duplicates and replicates.
The QC procedure for historical diamond and RC samples is unknown but considered immaterial.
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.
Sample duplicates from the historical drilling were taken from selected intervals and compared to the original assay. Quarter core
was taken for diamond samples and riffle resplits for RC samples.
Whether sample sizes are appropriate to the grain size of the
material being sampled.
The samples sizes at Commonwealth are considered appropriate since gold has been identified as predominantly fine-grained by
thin section analysis which would indicate the nugget effect is minimal.
The nature, quality and appropriateness of the assaying and
laboratory procedures used and whether the technique is
considered partial or total.
An industry standard fire assay technique for samples using lead collection with an Atomic Absorption Spectrometry (AAS) finish
was used for gold and aqua regia digest for base metals and silver.
The quality of historical drill sample assays is unknown, however this is considered immaterial at this stage of exploration.
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.
No geophysical tools were used to determine material element concentrations. A handheld XRF was used for qualitative analysis
only.
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.
For the rock chips, quality control procedures for assays were followed via internal laboratory protocols. Accuracy and precision
are within acceptable limits.
The quality control of historical drill sample assays is unknown, however this is considered immaterial at this stage of exploration.
The verification of significant intersections by either independent
or alternative company personnel.
Significant intersections from drilling have not been verified by independent or alternative companies. This is not required at this
stage of exploration.
Criteria
Location of data
points
JORC Code explanation
Commentary
The use of twinned holes.
Two twin diamond holes versus historic RC holes have been drilled at Commonwealth South and Main Shaft.
Documentation of primary data, data entry procedures, data
verification, data storage (physical and electronic) protocols.
Primary assay data for rock chips has been entered into standard Excel templates for plotting in Mapinfo and Target. All historical
drill 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.
Accuracy and quality of surveys used to locate drillholes (collar
and down-hole surveys), trenches, mine workings and other
locations used in Mineral Resource estimation.
Recent drill holes have been located by DGPS. Historical drill holes and mine shafts have been verified by DGPS.
Specification of the grid system used.
The grid system for Commonwealth is MGA_GDA94, Zone 55.
Quality and adequacy of topographic control.
Standard government topographic maps have been used for topographic validation. The DGPS is considered sufficiently accurate
for elevation data.
For the diamond holes, down-hole single shot surveys were conducted by the drilling contractor. Surveys were conducted at 6m,
18, 30m and then approximately every 30m down-hole.
For the RC drill holes, downhole dip surveys were taken at approximately 30m intervals and at the bottom of the hole.
Data spacing for reporting of Exploration Results.
Drill spacing of drill holes ranges between 10 and 30 m which is considered adequate for 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.
Drill spacing of drill holes ranges between 10 and 50 m and may be considered adequate for Mineral Resource and Ore reserve
estimation procedures. However estimations of grade and tonnes have not yet been made.
Whether sample compositing has been applied.
Sample compositing has been applied for quoting drill composite results only.
Whether the orientation of sampling achieves unbiased sampling
of possible structures and the extent to which this is known,
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