Multiple high-grade gold intercepts at St Arnaud Comstock
ASX ANNOUNCEMENT
24 JULY 2025
MULTIPLE HIGH-GRADE GOLD INTERCEPTS AT
ST ARNAUD COMSTOCK
ST ARNAUD – COMSTOCK PROJECT HIGHLIGHTS
Mineralisation with multiple gold intercepts, outside the existing resource, supports further
potential at depth
Highlight results from 25NED001 include:
○ 6.9m @ 4.24g/t Au from 422.1m
(incl. 0.75m @ 18.6 g/t Au from 422.1m)
○ 3.2m @ 4.71g/t Au from 434.0m
(incl. 0.6m @ 19.9g/t Au from 435.9m)
(see Table 1 for full outline of results received)
Mineralisation is down dip of previous high-grade intercepts, and outside of the maiden
Inferred Mineral Resource and Exploration Target reported in June 20251.
Gold intercepts demonstrate ongoing mineral continuity and further potential to expand the
existing gold resource inventory.
Mineralisation associated with sheared stylolitic quartz veins with elevated sulphides
including pyrite, arsenopyrite, galena and sphalerite.
Diamond drilling program at Comstock remains ongoing with a single rig targeting further
down dip and down plunge extensions to the known mineralisation.
Management
Comment
“It’s extremely positive to see mineralisation
continuity down dip along the main Comstock
shear at St Arnaud. The elevated grade intercepts
have potential to rapidly add to our already
substantial global resource inventory, including at
St Arnaud. We look forward to seeing the results
from the ongoing program.”
- James Gurry, Managing Director
1
Aureka Limited ASX Release: St Arnaud Maiden JORC MRE and Exploration Target – Amended, 13 June 2025
A S X : AK A
BRINGING VICTORIA'S GOLD TO LIFE
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24 JULY 2025
Cautionary Statement
The potential quantity and grade of the Exploration Target set out in Table 3 on page 6 of this
release is conceptual in nature. There has been insufficient exploration to date to estimate a
Mineral Resource, and it is uncertain if further exploration will result in the estimation of a
Mineral Resource. The Exploration Target has been prepared and reported in accordance with
the 2012 edition of JORC Code.
ST ARNAUD – COMSTOCK PROJECT, HIGHLIGHTS
First results from diamond drilling program at the St Arnaud Comstock project identifies
down-dip mineralisation continuity with multiple gold intercepts.
Key results from 25NED001 are summarised with full results refer to Table 1 on page 3:
3.75m @ 1.02g/t Au from 297.75m
4.4m @ 0.62g/t Au from 402m
3.35m @ 1.87g/t Au from 408.1m
4.0m @ 1.14g/t Au from 415.0m
6.9m @ 4.24g/t Au from 422m (incl. 0.75m @ 18.6 g/t Au from 422.1m)
3.2m @ 4.71g/t Au from 434.0m (incl. 0.6m @ 19.9g/t Au from 435.9m)
2.0m @ 1.88g/t Au from 454.0m
Mineralisation is down dip of previous high-grade intercepts and outside of the maiden
Inferred Mineral Resource reported in June 20251.
Mineralisation associated with sheared stylolitic quartz veins with elevated sulphides
including pyrite, arsenopyrite, galena and sphalerite.
The multiple gold intercepts highlight the down dip Au fertility of the Comstock shear and
demonstrates ongoing mineral continuity and with further drilling has high potential to
expand the Maiden Resource at St Arnaud that was reported earlier this year.
Drilling successfully intersected the targeted extension of the Comstock quartz reef
systems and associated sulphide assemblage of pyrite, chalcopyrite, galena and sphalerite,
which are thought to be related to the localised higher >18g/t Au grades.
The ongoing drilling program at Comstock aims to continue targeting additional down dip
and down plunge extensions of the Comstock reef system and expand upon the maiden
inferred resource.
1
Aureka Limited ASX Release: St Arnaud Maiden JORC MRE and Exploration Target – Amended, 13 June 2025
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Table 1 – Summary of key assays returned from 25NED001 AKA’s first hole drilled at St Arnaud
Hole ID
25NED001
25NED001
25NED001
25NED001
25NED001
25NED001
25NED001
25NED001
A S X : AK A
Sample ID
From (m)
To (m)
Interval (m)
Au (g/t)
AKA000648
297.75
298
0.25
8.46
AKA000649
298
298.45
0.45
0.36
AKA000651
298.45
298.85
0.4
0.63
AKA000652
298.85
299.8
0.95
0.64
AKA000653
299.8
300.55
0.75
0.33
AKA000655
300.55
301.5
0.95
0.48
AKA000766
402
403
1
0.52
AKA000767
403
404
1
0.23
AKA000768
404
404.6
0.6
0.33
AKA000769
404.6
405.3
0.7
0.33
AKA000770
405.3
405.75
0.45
0.7
AKA000771
405.75
406.4
0.65
1.87
AKA000774
408.1
409.05
0.95
0.25
AKA000775
409.05
409.76
0.71
1.57
AKA000776
409.76
410.4
0.64
3.85
AKA000777
410.4
411.05
0.65
2.87
AKA000778
411.05
411.45
0.4
1.37
AKA000784
415
416
1
0.33
AKA000785
416
417
1
2.07
AKA000786
417
418
1
1.62
AKA000787
418
419
1
0.54
AKA000791
422.1
422.85
0.75
18.6
AKA000792
422.85
423.9
1.05
1.36
AKA000793
423.9
425
1.1
5.6
AKA000794
425
426
1
0.81
AKA000795
426
427
1
1.03
AKA000796
427
428
1
1.79
AKA000797
428
429
1
4.12
AKA000803
434
435
1
0.43
AKA000804
435
435.9
0.9
2.01
3.2m @ 4.71g/t Au from 434m
AKA000805
435.9
436.5
0.6
19.9
(incl.0.60m @ 19.9g/t Au)
AKA000806
436.5
437.2
0.7
1.26
AKA000809
438
439
1
0.22
AKA000810
439
440
1
0.53
AKA000812
440
441
1
1.08
AKA000813
441
442
1
0.25
AKA000814
442
443
1
0.35
AKA000827
454
455
1
1.56
AKA000828
455
456
1
2.2
BRINGING VICTORIA'S GOLD TO LIFE
Comment
3.75m @ 1.02g/t Au from 297.75m
4.4m @ 0.62g/t Au from 402m
3.35m @ 1.87g/t Au from 408.1m
4m @ 1.14g/t Au from 415m
6.9m @ 4.24g/t Au from 422.1m
(incl.0.75m @ 18.6g/t Au)
5m @ 0.49g/t Au from 438m
2m @1.88g/t Au from 454m
3
24 JULY 2025
A
B
Figure 1 – Examples of high-grade drill intercept from Comstock Prospect DD hole 25NED001 (refer Table 1 on
page 3 for full details of assay results). A) Tray 125 B) Tray 129.
The St Arnaud Comstock Project
The Comstock prospect sits on the eastern margin of the Stawell Geological zone of the Lachlan
Orogen within the Saint Arnaud Group metasediments, which are unfossiliferous, quartz rich
turbidites assumed to be Cambro-Ordovician in age. Comstock is located within the historic St
Arnaud Goldfields along the Nelson line of reef and is situated approx. 2km north of the
township of St Arnaud.
Locally, the geology of the Comstock project consists of a package of tightly folded turbidites
with distinct shale and sandstone layers of varying thicknesses. The area is dominated by a
NNW trending, west dipping fault/shear zone known as the Comstock Shear. The shear zone is
interpreted to lie within the hinge zone of a large-scale syncline and is confined by a wide, shale
dominant zone of sediments. Shale directly adjacent to the shear zone tends to be highly
carbonaceous and very dark grey to black in colour. Course euhedral pyrite crystals seem to be
syngenetic to this carbon rich zone of fine sediments, quartz veining is associated with gold
mineralisation and is massive to stylolitic in texture.
Primary gold mineralisation at St Arnaud is hosted within quartz veins which are structurally
controlled within very complex structural domains associated with folding and NNW trending,
west dipping thrust faults. Gold mineralisation is hosted by quartz reef systems within brittle
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fractures and faults and can extend from a few metres long to a few kilometres along strike but
usually a few hundred metres. These NNW trending reefs have steep plunging gold shoots. The
mineralisation has a base metal signature of Au + As + Ag + Pb. In historical records, the gold
ore was characterised by a relatively high sulphide content up to 5% pyrite, chalcopyrite,
arsenopyrite, galena and silver. Most of the mines stopped at the oxide-sulphide interface due
to reduced grade and poor recoveries from sulphide ores
The quartz reef systems can extend for a few metres to a few kilometres along strike but are
usually a few hundred metres strike length. There appears to be an association with greenblack carbonaceous shales and higher gold grades.
Figure 2 – 25NED001 intercepts with legacy drill results at Comstock within the Nelson Line1.
Navarre Minerals Limited ASX Release: Maiden Diamond Drilling on St Arnaud’s Nelson Line Intersects Broad Gold and Silver
Mineralisation, 21 January 2022
1
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24 JULY 2025
Maiden Mineral Resource
In June 2025 AKA released a maiden JORC Mineral Resource Estimate (MRE) of 1.45M tonnes at
1.21g/t Au for 56,500 oz gold has been determined (Table 2) and additionally, an exploration
target around the inferred resource has been estimated to range between 3.0Mt and 3.5Mt, at
grades 1.2g/t to 1.0g/t resulting in an exploration target range estimate of 112koz to 116koz of
gold and potentially economic amounts of silver at a grades of 1.9g/t to 2.02g/t Ag for total of
195koz to 214koz silver (Table 3).
Table 2 – Comstock Project Mineral Resource Estimate in accordance with the 2012 edition of JORC Code1.
Cut-Off
Prospect
Gold
Inferred
Tonnes
(g/t)
Comstock (St
>0.5
Gold Grade
Gold
Grade
Silver
(g/t)
Ounces
(g/t)
(oz)
silver
1,450,000
1.21
56,500
2.14
100,00
Arnaud)
The preceding statements of Mineral Resources conforms to the Australasian Code for Reporting of Exploration Results, Mineral
Resources and Ore Reserves (JORC Code) 2012 Edition. All tonnages reported are dry metric tonnes. Minor discrepancies may occur
due to rounding to appropriate significant figures.
Table 3 – Comstock Project estimated Exploration Target in accordance with the 2012 edition of JORC Code2.
Exploration Target*
Prospect
Comstock (St
Arnaud)
Range
Tonnes
Gold
Gold
Silver
Silver
(Mt)
Grade
ounces (k
Grade
ounces (k
(g/t)
Oz)
(g/t)
Oz)
Lower
3.0
1.2
116
2.02
195
Upper
3.5
1.0
112
1.90
214
The potential quantity and grade of the Exploration Target is conceptual in nature and there has been insufficient exploration to
estimate a Mineral Resource in relation to this Exploration Target. It is uncertain if further exploration will result in the estimation
of a Mineral Resource in relation to these Exploration Targets.
Potential for further growth in Aureka’s global resource inventory
The assay results from 25NED001 have confirmed the presence of Au mineralisation outside of
the maiden JORC MRE and demonstrates the ongoing potential for further growth to AKA’s
global resources. Several zones of significant Au mineralisation were intersected along the main
Comstock shear structure approx. 190m down dip of legacy diamond drill hole NED015 (6.4m
@ 1.3g/t Au) and 230m down dip of NED009 (4.6m @ 3.2g/t Au). The mineralisation within
25NED001 was associated with increased pyrite, chalcopyrite, galena and sphalerite. Localised
higher >18g/t assays are identified to occur within shear and tensional quartz-pyrite veins.
Along with down dip continuity, significant Au intercepts further support a proposed steep
plunging ore shoot.
1
2
Aureka Limited ASX Release: St Arnaud Maiden JORC MRE and Exploration Target – Amended, 13 June 2025
Aureka Limited ASX Release: St Arnaud Maiden JORC MRE and Exploration Target – Amended, 13 June 2025
A S X : AK A
BRINGING VICTORIA'S GOLD TO LIFE
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24 JULY 2025
Figure 3 – Comstock plan view maiden resource outline with mineralisation trends and core drill hole traces1.
Navarre Minerals Limited ASX Release: Maiden Diamond Drilling on St Arnaud’s Nelson Line Intersects Broad Gold and Silver
Mineralisation, 21 January 2022
1
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24 JULY 2025
Comstock - Proximity to a number of operating gold mills
St Arnaud Gold Project and the Comstock pit lies within trucking distance to a number of gold
processing plants in Victoria. With the current strong gold price environment Aureka intends to
begin community, scoping and regulatory approval work to plan for a productive future at
Comstock and the St Arnaud gold field.
Figure 4 – St Arnaud Comstock Project relative location to a number of gold processing mills in Victoria.
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Figure 5 – Aureka team survey’s the Comstock pit at St Arnaud.
This announcement has been approved for release by the Board of Directors.
For further information, please visit www.aureka.com.au, or contact:
James.Gurry@aureka.com.au
Managing Director
Ph: (03) 9692 7222
peter@nwrcommunications.com.au
Investor and Media Relations
Ph: 0412 036 231
Aureka uses InvestorHub for enhanced, 2-way, communication with shareholders, providing
easy access to Company updates, reports, and announcements. Investors are encouraged to
sign up to the InvestorHub distribution list on the Company’s website. Sing up here:
https://investorhub.aureka.com.au/
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Competent Persons Statements
The information in this announcement that relates to exploration results, data quality,
geological interpretations, Mineral Resources and Ore Reserves statements and Exploration
Target potential statements for the St Arnaud Comstock Gold Project is based on, and fairly
represents, information compiled by Mr. Daniel Brost BSc (Economic Geology) - MSc (Mine
Engineering). Mr. Brost is not employed by Aureka Limited and has acted as an independent
consultant on the Comstock Prospect Mineral Resource estimation. Mr. Brost is a Chartered
Professional Geology and a Member of the Australasian Institute of Geologists (#221836) and
has sufficient experience with the style of mineralisation, the deposit type under consideration
and to the activities undertaken to qualify as a Competent Person as defined in the 2012 Edition
of the “Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore
Reserves (The JORC Code). Mr. Brost consents to the inclusion in this report of the contained
technical information relating the Mineral Resource Estimation in the form and context in which
it appears.
Exploration Target – Comstock Project
On 13 June 2025, AKA announced the maiden gold Exploration Target at its 100%-owned St
Arnaud Comstock project in Victoria, Australia. Notably, the Exploration Target was constrained
to the current drill footprint at Comstock, as at the time this was the only area that contained
sufficient drilling to determine continuity and infer grade ranges. Significant potential exists to
increase the size of the exploration target with additional drill results beyond the Exploration
Target area.
The potential quantity and grade of the Exploration Target is conceptual in nature and therefore
is an approximation. There has been insufficient exploration to estimate a Mineral Resource,
and it is uncertain if further exploration will result in the estimation of a Mineral Resource. The
Exploration Target has been prepared and reported in accordance with the 2012 edition of the
JORC Code.
Summary of Relevant Exploration Data, Methodology, and Assumptions
The Comstock Shear Lode/veins are considered to have sufficient data to prepare an
Exploration Target estimate, using extrapolated mineral resource search distance within the
solids and the mapped strike length as a base case for determining overall strike length.
Historical surface occurrences, soil geochemistry and historical geophysical report were also
used for the establishment of a clear Exploration Target in the Comstock Prospect.
The strike length was adjusted using the proportion of positive intersections to estimate the
mineralised strike length of each shear structure. Each lode/vein was extrapolated up to 500
metres depth at a dip of -75° to -90o based on the continuity of similar deposits in the Victoria
goldfields, and a ‘base case’ estimation of tonnes and grade was applied to each reef.
The base case was used to approximate a range of tonnages and grades for the Exploration
Target estimate shown in Table 2 of the report, in accordance with the JORC Code (2012). The
ranges were derived from expected upper and lower volumes for the dominant rock types in
each shear structure and the 90% confidence interval for declustered true thickness and
historical mining and sampled drill hole grade data. The grade range was estimated based on
the 90% confidence interval of the grade of the positive shear intersections.
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Lode Attributes
Attribute
Walker Lode/ Vein
Walker Shear
Data Mean grade of 1.18 g/t
intersections >=0.5
(incl. internal waste)
g/t gold
1.04 g/t
1.26 g/t
(incl. internal waste)
(incl.
waste)
Average apparent 2m – 3m
thickness
1.5m-2m
2m-3.5m
(1 m
length)
Comstock Shear/Lode
internal
minimum
Rock
Association
Type Turbidite- Shale-Siltstone Turbidite
Shale- Turbidite - Shaleassemblage
Siltstone assemblage
Siltstone
assemblage
Strike
Extrapolation
300m NW @ 336o
Dip Extrapolation
200m @ -78 o from 0 RL
Probability
positive
intersection
200m SE @ 156o
50m SE@ 180o
200m @ -78 o from 0 RL
100m @ -90
from 0 RL
50%
34%
200m SE @ 156o
of 64%
*Notes: The potential quantity and grade of the gold mineralisation at the wider Comstock
project is conceptual in nature, there has been insufficient exploration to estimate a Mineral
Resources, and it is uncertain if further exploration will confirm the target ranges.
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APPENDIX A
Table 1. St Arnaud Comstock Diamond Drill Hole Collar Location and Drilling Results >0.20 g/t Au.
Hole ID
25
NED001
Easting
(MGA)
701115
Northing
(MGA)
5947840
A S X : AK A
RL
(AHD)
253
Azimuth
(MGA)o
249.9
Dipo
-60
Depth
(m)
461.2
Sample ID
From
To
Interval
(m)
Grade
(g/t)
Au
AKA000404
42.68
42.98
0.3
0.25
AKA000437
76.85
77.05
0.2
0.61
AKA000571
225
226
1
0.29
AKA000645
296.3
297.3
1
0.23
AKA000648
297.75
298
0.25
8.46
AKA000649
298
298.45
0.45
0.36
AKA000651
298.45
298.85
0.4
0.63
AKA000652
298.85
299.8
0.95
0.64
AKA000653
299.8
300.55
0.75
0.33
AKA000655
300.55
301.5
0.95
0.48
AKA000662
306.4
307.15
0.75
0.58
AKA000668
311.6
312
0.4
0.24
AKA000669
312
313
1
0.23
AKA000680
323
324
1
0.49
AKA000703
345
346
1
0.5
AKA000708
349.6
350.73
1.13
0.39
AKA000719
360
360.8
0.8
0.49
AKA000720
360.8
362
1.2
0.73
AKA000729
369
370
1
0.3
AKA000743
381
382
1
0.52
AKA000744
382
383
1
0.24
AKA000766
402
403
1
0.52
AKA000767
403
404
1
0.23
AKA000768
404
404.6
0.6
0.33
AKA000769
404.6
405.3
0.7
0.33
AKA000770
405.3
405.75
0.45
0.7
AKA000771
405.75
406.4
0.65
1.87
AKA000774
408.1
409.05
0.95
0.25
AKA000775
409.05
409.76
0.71
1.57
AKA000776
409.76
410.4
0.64
3.85
AKA000777
410.4
411.05
0.65
2.87
AKA000778
411.05
411.45
0.4
1.37
AKA000781
412.8
413.9
1.1
0.58
AKA000784
415
416
1
0.33
AKA000785
416
417
1
2.07
AKA000786
417
418
1
1.62
BRINGING VICTORIA'S GOLD TO LIFE
Comment
3.75m @
1.02g/t Au
from 297.75m
4.4m @
0.62g/t Au
from 402m
3.35m @
1.87g/t Au
from 408.1m
4m @ 1.14g/t
Au from
415m
12
24 JULY 2025
AKA000787
418
419
1
0.54
AKA000789
420
421
1
0.22
AKA000791
422.1
422.85
0.75
18.6
AKA000792
422.85
423.9
1.05
1.36
AKA000793
423.9
425
1.1
5.6
AKA000794
425
426
1
0.81
AKA000795
426
427
1
1.03
AKA000796
427
428
1
1.79
AKA000797
428
429
1
4.12
AKA000801
432
433.1
1.1
0.21
AKA000803
434
435
1
0.43
AKA000804
435
435.9
0.9
2.01
AKA000805
435.9
436.5
0.6
19.9
AKA000806
436.5
437.2
0.7
1.26
AKA000809
438
439
1
0.22
AKA000810
439
440
1
0.53
AKA000812
440
441
1
1.08
AKA000813
441
442
1
0.25
AKA000814
442
443
1
0.35
AKA000820
448
449
1
0.43
AKA000821
449
450
1
0.25
AKA000823
450
451
1
0.6
AKA000825
452
453
1
0.33
AKA000827
454
455
1
1.56
AKA000828
455
456
1
2.2
AKA000830
457
458
1
0.21
AKA000831
458
459.1
1.1
0.49
6.9m @
4.24g/t Au
from 422.1m
3.2m @
4.71g/t Au
from 434m
5m @ 0.49g/t
Au from
438m
2m @1.88g/t
Au from
454m
The Comstock Project diamond drill program was undertaken by AMWD Pty Ltd.
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APPENDIX B
St Arnaud: Comstock Gold Project
JORC Code, 2012 Edition - Table 1
Section 1 Sampling Techniques and Data
Criteria
Sampling
techniques
JORC Code explanation
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.
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 (eg submarine
nodules) may warrant disclosure of
detailed information.
Commentary
Air Core & Reverse Circulation Drilling
All air-core (AC) drill holes have been
routinely sampled at 1m intervals
downhole directly from a rig mounted
cyclone. Each metre is collected and
placed on a plastic sheet on the ground
and preserved for assay sub-sampling
analysis as required. For RC, each metre
of sampling is collected in individual
sequentially numbered plastic bags and
preserved.
Sub-samples for assaying are generated
from the 1m preserved samples and
have been prepared at the drill site by
either a spear sampling method (AC) or
riffle split (RC) based on logged geology
and mineralisation intervals. Subsamples have been taken at 1m
intervals or as composites ranging from
2-5m intervals ensuring a sample
weight of between 2 to 3 kg per subsample.
Certified reference material and sample
duplicates have been inserted at regular
intervals with laboratory sample
submissions.
Diamond Core Drilling
The diamond drill core samples are
selected on geological intervals varying
from 0.2m to 1.3m in length.
All drill core is routinely cut in half
(usually on the right of the marked
orientation line) with a diamond saw
and submitted for analysis.
Representative sampling is ensured by a
combination of Company procedures regarding
quality control (QC) and quality assurance/
Testing (QA). Certified standards and blanks are
routinely inserted into assay batches.
A S X : AK A
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Drilling
techniques
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).
Air Core (AC) Drilling
Legacy AC drilling has been carried out
using a Wallis Mantis 80 AC rig mounted
on a Toyota Landcruiser base. The AC
rig used a 3.5” blade bit to refusal,
generally just below the fresh rock
interface.
Reverse Circulation Drilling
Legacy RC drilling has been conducted
using a track-mounted drill rig; 400psi
900cfm compressor and booster;
auxiliary compressor where dictated by
water in-flows. The RC rig used a 4”
diameter RC hammer with 110mm
button bit to progress the hole to
design depth or where groundwater
inflows compromise sample quality.
Diamond Core Drilling
Legacy diamond drilling was conducted
using Deepcore track-mounted LM90
and LF130.
Pre-collars have been drilled to solid
bedrock using an HWT (114.3mm) drill
bit followed by diamond coring with a
diameter of 63.5mm (HQ)
Diamond drilling of HQ3 (triple-tube) is
undertaken to ensure maximum core
recovery.
Drilling completed by Aureka was
conducted by AMWD
Pre-collars
were
drilled
to
solid
bedrock using an HQ3 drill bit (93mm
hole diameter) coring down to solid
rock followed by HWT casing diamond
(114.3mm hole diameter)
Diamond drilling of HQ3 (triple-tube)
was undertaken to ensure maximum
core recovery.
Drill core has been orientated with a
Reflex ACT III core orientation tool then
continuously marked with a line while
on an angle iron cradle
Drill sample
recovery
A S X : AK A
Method of recording and assessing core
and chip sample recoveries and results
assessed.
Measures taken to maximise sample
recovery and ensure representative
nature of the samples.
Whether a relationship exists between
sample recovery and grade and whether
sample bias may have occurred due to
Air Core & Reverse Circulation Drilling
Legacy AC & RC drill recoveries have been
visually estimated as a semi-quantitative
range and recorded in the log.
Recoveries are generally high (>90%), with
reduced recovery in the initial near-surface
sample.
Samples are generally dry, but many became
wet at the point of refusal in hard ground
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preferential loss/gain of fine/coarse
material.
below the water table.
Geological control maintained at the drill site
at all times to ensure drilling and sampling is
to required standard.
No sampling issue, recovery issue or bias has
been picked up and is considered that both
sample recovery and quality is adequate for
the drilling technique employed.
Diamond Core Drilling
All diamond core has been logged
capturing any core loss, if present, and
recorded in the database.
All drill depths are checked against the
depth provided on the core blocks and
rod counts are routinely carried out by
the driller.
Logging
Sub-sampling
techniques
and sample
preparation
A S X : AK 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.
The total length and percentage of the
relevant intersections logged.
If core, whether cut or sawn and whether
quarter, half or all core taken.
If non-core, whether riffled, tube
sampled, rotary split, etc and whether
sampled wet or dry.
For all sample types, the nature, quality
and appropriateness of the sample
preparation technique.
Quality control procedures adopted for
all sub-sampling stages to maximise
representivity of samples.
Measures taken to ensure that the
sampling is representative of the in situ
material collected, including for instance
results for field duplicate/second-half
sampling.
Whether sample sizes are appropriate to
the grain size of the material being
sampled.
Core recovery for the areas sampled is generally
good.
Geological logging of samples follows
Company and industry common practice.
Qualitative logging of samples includes (but
is not limited to), lithology, mineralogy,
alteration, veining and weathering.
All logging is quantitative, based on visual
field estimates.
Most if all AC & RC chips and core were
photographed in detail.
For AC & RC, a small representative sample
has been retained in a plastic chip tray for
future reference and logging checks.
Detailed chip logging, with digital capture,
has been conducted for 100% of chips logged
by previous geological teams.
Detailed core logging, with digital capture
and digital photography, was conducted for
100% of the recent Aureka diamond drilling
Air Core & Reverse Circulation Drilling
Procedures have been followed to ensure
sub-sampling adequacy and consistency.
These included (but are not limited to), daily
workplace inspections of sampling
equipment and practices.
Only recent core drilling incorporated blanks
and certified reference materials are
submitted with the samples to the laboratory
as part of the quality control procedures.
AC composite, 1m individual and EOH
samples have been collected as grab
samples.
Legacy drill sample preparation and base
metal and precious metal analysis is
undertaken by a registered laboratory (ALS
Perth, WA). Sample preparation by dry
pulverisation to 85% passing 75 microns is
undertaken by ALS Adelaide, SA.
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The sample sizes are considered appropriate
to correctly give an accurate indication of
mineralisation given the qualitative nature of
the technique and the style of gold
mineralisation sought.
Diamond Core Drilling
Detailed diamond core logging, with
digital capture, has been conducted for
100% of the core by previous geological
team.
Half core is sampled from NQ and HQ
diameter drill core.
Company procedures have been
followed to ensure sub-sampling
adequacy and consistency. These
included (but are not limited to), daily
workplace inspections of sampling
equipment and practices.
Blanks and certified reference materials
are submitted with the samples to the
laboratory as part of the quality control
procedures.
No second-half sampling has been
conducted at this stage.
Quality of
assay data
and laboratory
tests
A S X : AK A
The nature, quality and appropriateness
of the assaying and laboratory
procedures used and whether the
technique is considered partial or total.
For geophysical tools, spectrometers,
handheld XRF instruments, etc, the
parameters used in determining the
analysis including instrument make and
model, reading times, calibrations factors
applied and their derivation, etc.
Nature of quality control procedures
adopted (e.g. standards, blanks,
duplicates, external laboratory checks)
and whether acceptable levels of
accuracy (i.e. lack of
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