Alkane Extends High Grade Gold Trend at Brunswick
CONTACT: NIC EARNER, MANAGING DIRECTOR & CEO, ALKANE RESOURCES LTD, TEL +61 8 9227 5677
INVESTORS & MEDIA: NATALIE CHAPMAN, CORPORATE COMMUNICATIONS MANAGER, TEL +61 418 642 556
Level 4, 66 Kings Park Rd, West Perth WA 6005, AUSTRALIA (PO Box 768, West Perth WA 6872, AUSTRALIA)
Telephone: +61 8 9227 5677 alkres.com [email protected]
INVESTOR ANNOUNCEMENT and
MEDIA RELEASE
14 July 2026
Alkane Extends High Grade Gold Trend at
Brunswick South
Perth, Western Australia - Alkane Resources Limited (ASX: ALK; TSX: ALK; OTCQX: ALKRY) (‘Alkane’
or ‘the Company’) is pleased to announce the latest exploration results for extension and infill drilling of
the Brunswick South deposit, located 400m south of the previously mined Brunswick vein and 200m from
planned underground access at its Costerfield Operation in central Victoria, Australia.
Program Summary
An additional 91 holes targeting the Brunswick South deposit have been drilled since Alkane’s previous
update (ASX announcement 15 October 2025 titled ‘Costerfield Resource and Reserve Statement)
Confidence in grade continuity has been supported by the drilling with the identi fication of a high
antimony and gold grade connection between the recently discovered gold dominant zone at depth
and the historical surface workings.
Drilling is continuing to identify extensions to the deeper gold dominant zone (Kiwi zone) with recent
geological interpretation indicating the setting for mineralisation is similar to that of the Youle deposit
currently being mined.
Additionally, parallel veining has been intercepted approximately 200m to the west of Brunswick South
with follow-up drilling scheduled to commence shortly.
An updated Mineral Resource Estimation with initial Ore Reserve is due to be released later in the
year.
Brunswick South Assay Highlights
Brunswick South Vein:
o 50.1g/t gold and 26.2% antimony over 2.17m (ETW 1.08m) in BD468
o 109.9g/t gold and 3.1% antimony over 0.65m (ETW 0.62m) in BD433
o 50.2g/t gold and 33.3% antimony over 0.86m (ETW 0.62m) in BD424
o 39.8g/t gold and 0.7% antimony over 1.3m (ETW 1.15m) in BD408
o 25g/t gold and 0% antimony over 1.7m (ETW 1.64m) in BD513 (Kiwi zone)
o 21.6g/t gold and 6.7% antimony over 1.65m (ETW 0.92m) in BD496
Note. ETW refers to the estimated true width of the veining.
Alkane Managing Director & CEO, Nic Earner, said:
“Focused extension and infill drilling at Brunswick South over the previous year has produced highly
encouraging results. This newly defined deposit not only contains pockets of high gold endowment, but
critically a significant quantity of antimony. Exciti ngly Brunswick South can be brought online without
extensive access requirements as it is situated 200m from existing development. We are commencing
development towards Brunswick South in the current quarter and are looking to establish it as a primary
production source for Costerfield.”
Alkane Extends High Grade Gold Trend at Brunswick South Deposit, Costerfield – 14 July 2026
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Costerfield Gold-Antimony Field
Alkane Resources Ltd 100%
The Costerfield gold-antimony deposit was discovered in 1861, antimony having been already identified in
the district as early as 1853 as prospectors attracted to the McIvor (Heathcote) alluvial gold rush began to
explore the surrounding hills for the primary deposits. Several lodes along a 3k m corridor were rapidly
opened up, the bulk of historical production coming from leases at the northern end of the field; the
Costerfield (Main), Bombay and Minerva mines. Production from these mines primarily took place in two
phases, between 1861-1883 and 1903-1924, and a short-lived attempt at redeveloping the mine occurred
between 1933-1939.
Modern mining has been continuous since 2006, when Australian Gold Development commenced
underground operations at Augusta , at the southern end of the field. AGD’s Costerfield operation was
purchased by Mandalay Resources in 2010, and extraction of the vertically continuous vein system has
progressively moved north beneath the Costerfield, Minerva and Bombay group of mines , where
Mandalay’s high-grade Youle and Shepherd lodes were discovered.
The Brunswick deposit was discovered in early 1863 (initially called the New Brunswick) and saw limited
prospecting through the early life of the field. It was not until the investigations of Mid-East Minerals and
the Geological Survey of Victoria between 1966- 1971 that the extent of mineralisation at the deposit was
intently explored via diamond drilling and the sinking of an exploratory shaft which saw the development
of two levels later throughout the 1970s. Australian Gold Development later developed an open cut mine
on the Brunswick Reef , extracting oxide gold in 1995-1997. Mandalay Resources mined the Brunswick
Reef below the historic workings via underground development in 2018, while developing north from
Cuffley to the newly discovered Youle Deposit.
Figure 1. Regional map of the Costerfield Project in GDA2020 grid showing Alkane tenements and the main
corridors of mineralisation identified, highlighting the location of the Brunswick South deposit.
Alkane Extends High Grade Gold Trend at Brunswick South Deposit, Costerfield – 14 July 2026
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A small, near -surface resource delineated by AGD at the time of open- cut mining exists approximately
400m south of the main deposit, which indicated strong structural continuity for the Brunswick deposit
outside of the mined area. This Brunswick South deposit remained resistant to significant extension via
diamond drilling down- dip, until mid-2025 when a campaign of three diamond holes all intersected high-
grade mineralisation over the span of 175m just below the level of the Cuffley-Brunswick access, prompting
immediate intensive infill and extension drilling (ASX announcement 15 October 2025 titled ‘Costerfield
Resource and Reserve Statement’). The previous high grade intercepts included:
76.6 g/t gold over 0.49m (ETW 0.44m) in BD387;
265.0 g/t gold and 0.7% antimony over 0.29m (ETW 0.17m) in BD388; and
52.3 g/t gold over 1.69m (ETW 1.58m) in BD391
Deposit Geology
The Brunswick Deposit is located at the apex of the Costerfield Dome, between the Augusta and Youle
deposits at Costerfield and offset approximately 500m west of the main corridor of mineralisation. The
Costerfield Formation host rocks are uniformly siltstones above approximately 900RL (300m below
surface), transitioning to thin bedded and fine-grained turbidites below this level. The mineralisation in the
north is hosted by a vertical shear that occupies the hinge of the gentle Brunswick Anticline, crossing to an
adjacent parasitic syncline in the new southern portion of the deposit. Mineralisation in the vertical, shear
hosted part of the deposit tends to be antimony -rich and proportionally deficient in quartz compared to
most other worked Costerfield veins, while retaining gold grades comparable to the rest of the field.
North-west trending, steeply dipping faults intersect the Brunswick shear and delineate high-grade shoots
within the orebody. This relationship is well understood in the northern part of the deposit where open- cut
mining took place and is expected to be important in the south. Bedding-parallel laminated quartz veins
and faults are common and influence ore grades at a local scale, the lode structure typically crosses these
structures without significant offset or deviation until the Kiwi Fault is reached. The Kiwi Fault is a bedding
parallel, laminated quartz fault where seen on the western limb of the Brunswick Anticline, which increases
in late, brittle damage and bifurcates into a duplex stack (with the Rooster Fault as its footwall) as it flattens
out over the crest of the anticline. In the northern end of the Brunswick deposit where the Brunswick shear
intersects the Kiwi Fault where it is almost horizontal , mineralisation splits into several parallel, vertical
veins bound between the Kiwi and Rooster fault planes that can achieve high grades albeit with limited ore
panel heights. In the new southern area where the Brunswick Shear intersects the fault in a position where
it dips moderately westward, mineralisation appears to roll into the fault plane and continue down- dip in a
fashion analogous to the Kendal vein system and high-grade Youle Lode in the northern end of the
Costerfield Main Corridor . The mineralisation so far encountered proximal to and with in the Kiwi Zone
differs significantly to the antimony-rich shear seen above, being predominantly free from stibnite and rich
in quartz. The gold-rich quartz veining is multiple-generation, containing early brecciated quartz healed by
a later quartz matrix.
Below the Rooster Fault, low-tenor mineralisation in the northern part of the deposit continues down dip in
a vertical shear of similar character to that above, offset approximately 80m to the west . This area to the
south has not been drill tested to date, and the mineralised Kiwi Fault plane is still being explored to
determine the extent of mineralisation.
Drilling Results
Since the previous release, 91 extension and infill holes have been completed, totalling 28,421m of
diamond drill core. In addition to extending the new high- grade zone, further infill of the existing historic
resource was conducted to identify possible economic continuity between the two areas, which appears to
be the case. Of the drilled holes, 10 intercepts have resulted in assays grading above 10g/t AuEq1 over a
diluted mining width of 1.8m:
1 AuEq calculated with assumptions: Au $/oz = 2,500; Sb $/t = 19,000; Au Recovery = 91% and; Sb Recovery = 92%
Alkane Extends High Grade Gold Trend at Brunswick South Deposit, Costerfield – 14 July 2026
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BD468 - 50.1g/t Au & 26.2% Sb over 2.17m (ETW 1.08m) (Figure 6)
BD433 - 109.9g/t Au & 3.1% Sb over 0.65m (ETW 0.62m)
BD424 - 50.2g/t Au & 33.3% Sb over 0.86m (ETW 0.62m)
BD408 - 39.8g/t Au & 0.7% Sb over 1.30m (ETW 1.15m)
BD513 - 25g/t Au & 0% Sb over 1.70m (ETW 1.64m) (Figure 7)
BD496 - 21.6g/t Au & 6.7% Sb over 1.65m (ETW 0.92m)
BD435 - 50.3g/t Au & 27.3% Sb over 0.55m (ETW 0.32m)
BD445 - 34.2g/t Au & 0% Sb over 0.74m (ETW 0.69m)
BD430 - 32.3g/t Au & 0% Sb over 0.93m (ETW 0.71m)
BD423 - 11.4g/t Au & 7.1% Sb over 1.54m (ETW 0.96m)
The drilling in hand has identified two main economic zones:
An upper shoot of high- grade antimony-gold mineralisation at the central-southern end of the
deposit, reaching from BD468 approximately 80m from surface down to BD496 at around 280m
below surface (~200m panel height), and;
A lower panel of gold- dominated mineralisation with a strike length approaching 400m, located
below the Penguin Fault, down to and including the Kiwi Fault (“Kiwi Zone” in this release)
Additional ore- grade intercepts were made centrally within the existing near-surface resource, building
confidence in the economic extents of the deposit as a whole. A general trend observed amongst the
economic-grade intercepts was the transition from antimony-rich intercepts in the upper level of the deposit
to gold dominated with lesser antimony approaching and within the Kiwi Zone. This trend is also observed
in the Youle/Shepherd system at a deeper level, which suggests that the zonation may occur on a per-
deposit basis rather than a field-wide gradient.
Many intercepts of smaller-scale splay veins associated with the Brunswick South structure were found,
the most notable of which was in BD463W2 with 288g/t Au over 0.16m (ETW 0.14m) located approximately
10m west of the main Brunswick South structure. These splays are likely to be systematically followed up
with additional holes from underground drilling platforms when mining reaches Brunswick South.
In addition to intercepts made on the main system a previously unknown line of mineralisation was
identified near surface, approximately 200 metres west of , and striking parallel to, the Brunswick deposit.
This Brunswick West target appears to dip 60-70 degrees east and is projected to intercept the Kiwi Zone
down-dip of where currently tested. While mineralisation is sporadic on the structure (small-scale structural
complexity and low drilling angles are contributing factors), an intercept of 8.4g/t gold and 1.3% antimony
over 0.32m (ETW 0.31m) was drilled in BD475 and is the deepest traverse of the line at ~220m below
surface.
Alkane Extends High Grade Gold Trend at Brunswick South Deposit, Costerfield – 14 July 2026
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Figure 2. Long Section of the Brunswick South deposit with major vein target envelopes displayed, recent drill
traces and > 6g/t AuEq new intercepts labelled. Older significant drill intercepts are displayed as smaller, unlabelled
icons.
Figure 3. Brunswick South Deposit Plan Section with recent drill traces and > 6g/t AuEq new intercepts labelled.
Older significant drill intercepts are displayed as smaller, unlabelled icons.
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Figure 4. Cross section of the Brunswick South deposit with the Costerfield Leapfrog geology model sliced at
5200N, where the greatest number of new high-grade intercepts are located. The spread of intercepts away
from the model slice is due to the strike of the Brunswick South deposit being approximately 15 degrees east
of mine grid north (as seen in Figure 3).
Alkane Extends High Grade Gold Trend at Brunswick South Deposit, Costerfield – 14 July 2026
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Figure 5. Core tray photograph of the Brunswick South intercept of BD468 (50.1g/t gold and 26.2% antimony
over 2.17m - ETW 1.08m) exhibiting the shear-associated, stibnite rich character typical to the Brunswick
deposit above the Kiwi Zone. Zonation of sulphide wallrock alteration, from fine grained arsenopyrite proximal
to the high grade veins to more distal blebby aggregates of pyrite may also be discerned. Photomicrographs
of gold clusters within quartz and stibnite from the richest segment of the intercept are also shown.
Alkane Extends High Grade Gold Trend at Brunswick South Deposit, Costerfield – 14 July 2026
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Figure 6. Tray photograph and gold grades of the Kiwi Zone in drillhole BD513. The mineralisation is quartz -
dominated in contrast to the upper Brunswick South structure, and occurs at a low angle to the west -dipping
bedding, following the Kiwi Fault plane. This is dissimilar to K-R mineralisation beneath Brunswick Main where
vertical veins are bound between the hangingwall and footwall planes of the fault slice due to the flattening of
the Kiwi and Rooster Fault structures, being more aligned with a Youle-like geometry.
Future Plans
The information presented in this release has been integrated into the Costerfield mine schedule, and the
commencement of capital development to access the area is scheduled for Q3 2026. Several targets
have emerged as priority for further testing, which include:
Further down-dip on the Kiwi Fault structure, which has not been effectively tested below 800RL to
date. Applying the Youle thrust -hosted model to the structure, changes in dip and strike may host
further economic pods of mineralisation, and Shepherd-like vertical veins suspected in the footwall
are also being tested for.
The gap in close-spaced drilling between the Brunswick and Brunswick South deposits will be tested
in the near future, as the presence of grade pods here will likely influence the positioning of capital
development.
Southern extension or repetition of grade pods. BD407, the southernmost testing hole of this program
stepped out 100 metres south of the previous bounding hole and intersected the Brunswick shear at
4884N. This intercept returned 9.4g/t gold over 0.30m (ETW 0.30m), demonstrating that the system
has strong structural continuity and may form further shoots of economic mineralisation in this
direction.
A previously unknown mineralised structure was intercepted near surface from western drilling
platforms. The best result to date from this structure is 8.4g/t gold and 1.3% antimony over 0.32m
(ETW 0.31m) in BD475. Structural and grade continuity where tested to date is somewhat weak,
although interpretation shows the vein to have a n easterly dip, leading to an intersection axis close
to the Brunswick South to Kiwi Zone transition. The highest prospectivity on this structure is likely
towards the south, which will be further tested later in the year when private land access is favourable.
An updated Brunswick South resource will be announced as part of Alkane’s upcoming Resource and
Reserves Statement.