REG - Greatland Resources - Exploration Update – West Dome Underground
Mon 07:45
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RNS Number : 7659D Greatland Resources Limited 11 May 2026
Greatland Resources Limited
E: info@greatland.com.au
W: https://greatland.com.au (https://greatland.com.au)
NEWS RELEASE | 11 May 2026
Exploration Update - West Dome Underground
Step-out drilling hits 58.7m @ 6.5g/t gold & 0.1% copper at Pinnacles
prospect 1.2km south of the West Dome Underground resource, indicates
extension of geological structure and stratigraphy
Highlights
· 1,858m exploration diamond drill hole (WRC14503A) recently
drilled from surface at the Pinnacles prospect, to test potential extension of
the geological structures and stratigraphy that host the West Dome Underground
(WDU) deposit, approximately 1.2km to the south of the current WDU Mineral
Resource Estimate (MRE).
· The Pinnacles drill hole intersected high grade mineralisation
and indicates a significant extension of the West Dome geological structure.
Assay results include the following significant intercepts:
· 58.7m @ 6.5g/t Au & 0.1% Cu from 1,754m (approximately true
width), including:
· 37.0m @ 9.98g/t Au & 0.14% Cu from 1,754m (approximately true
width); and
· 34.1m @ 1.1g/t Au from 1,820m.
· The mineralisation is open to the north towards the WDU, and to
the south, which is entirely untested. Further drilling is required to confirm
the tenor and extent of the mineralisation between the WDU and the Pinnacles
intersection, as well as to the south.
· This new intercept is situated approximately 1.5km from the
existing Telfer underground crusher and hoist infrastructure.
· Follow-up work to be completed includes:
· Wedge holes from drill hole WRC14503A, to test mineralisation
between 50-100m along strike and down dip.
· Planning for drilling between Pinnacles and WDU, and extension
drilling further south of Pinnacles.
Greatland Managing Director, Shaun Day, commented:
"It is a credit to our Exploration team to have first interpreted the
potential extension of the West Dome Underground at Pinnacles, a significant
distance from our current area of focus, and then to successfully plan and
execute this drill hole from surface to its target at depth.
"The wide high-grade mineralisation, including 58.7m @ 6.5g/t gold & 0.1%
copper (381.6 gram-metres gold), is among the best intercepts achieved from
West Dome Underground drilling to date.
"While the result is a single drill hole, it demonstrates the potential
extension of West Dome Underground mineralisation to the south of our current
resource. This new intercept is in similar proximity to our existing
underground crusher and hoist infrastructure as the current West Dome
Underground resource, further adding to its prospectivity.
"Further drilling will now be planned to test the existence and tenor of
mineralisation between the two zones."
Overview of the West Dome Underground projects
Greatland Resources Limited (Greatland or Company) (ASX:GGP, AIM:GGP) is
pleased to provide this exploration update on the West Dome Underground (WDU)
project.
The WDU emerged from the recognition that key geological structures hosting
mineralisation in the Main Dome Open Pit repeat in the West Dome Open Pit.
Accordingly, it was proposed that the geological features that are key to
mineralisation in the Main Dome Underground (Figure 1), may repeat below the
West Dome Open Pit.
The WDU was a high priority target identified by Greatland's due diligence
prior to the acquisition of Telfer. Following completion of the acquisition,
Greatland accelerated drilling in CY2025 from newly established underground
positions, with a total of 18,963m drilled to December 2025. Greatland's
drilling has confirmed that the key geological units hosting the Main Dome
Underground mineralisation are present in the WDU.
On 30 March 2026, Greatland announced a maiden Mineral Resource Estimate (MRE)
for WDU(1), comprising 8.0Mt @ 2.30g/t Au & 0.44% Cu for 0.6Moz Au &
35Kt Cu. The WDU MRE is contained within an anticline hinge and hosted across
two key domains: the high-grade sulphide replacement Lower Limey Unit (LLU)
and the broad mineralised Western Stockwork Corridor (WSC) (Figure 2).
Note 1: Refer to Greatland's 30 March 2026 announcement titled 'December 2025
Group Mineral Resource Statement
(https://app.sharelinktechnologies.com/announcement-preview/asx/7145fa048754370dc8ace609b1624100)
'.
Figure 1: Telfer December 2025 Mineral Resource schematic, showing location of
Pinnacles drill hole and closest historical intercepts.
Figure 2: West Dome Underground December 2025 Mineral Resource isometric view.
Pinnacles prospect
The Pinnacles prospect is located approximately 1km south of the West Dome
Open Pit and 1.2km south of the current WDU resource.(2)
Utilising the strong understanding of the Telfer geological structures and
stratigraphy from both the recent WDU drilling and historical shallower
drilling between the current WDU resource and the Pinnacles prospect, a 1.8km
diamond drilling (DD) drill hole was commenced from surface, targeting the
West Dome anticline hinge within the LLU stratigraphic layer. This target was
interpreted to lie approximately 1,750m downhole.
Drilling of diamond hole WRC14503A commenced in December 2025 and reached the
target depth in April 2026. Massive pyrite with ancillary chalcopyrite and
quartz veining, likely replacing the LLU, were intersected from 1,758m
downhole and extended to 1,772m, with interbedded sediments, quartz breccias
and narrow massive sulphides to 1,792m. Stockwork quartz veining and sulphides
continue to end of hole at 1,858m, and also occur 4m above the LLU contact,
commencing at 1,754m (Figures 3, 5).
Note 2: Drilling was described in Greatland's 22 January 2026 announcement
titled 'December 2025 Quarter Resource Development & Exploration
Activities Report
(https://app.sharelinktechnologies.com/announcement-preview/asx/592a47bc2043d65f43ff49ed991cc6e3)
'.
Figure 3: Core photos of top of mineralised section from 1,757.75m downhole to
1,782.2m showing the massive sulphide zone (red line) and the stockwork
mineralisation in sediments (blue line). Core is laid out top to bottom then
left to right.
The massive sulphide and interbedded sediments zone to 1,792m is interpreted
to correlate to the WDU LLU strata bound orebody containing the majority of
the current WDU resource. The stockwork breccia is similarly considered to be
the WDU vertical WSC in the core of the WDU anticline hinge below the LLU.
This interpretation is supported by the target stratigraphy and structure
being intersected within approximately 10m of its predicted down plunge
location, 1,200m down plunge of the current WDU resource.
Further evidence of the extension of the West Dome structure is from the
existence of several narrow reef style veins at around 1,640m downhole in the
Middle Malu formation above the LLU, which are of similar style to the
A-reef's at Main and West Dome.
The intercept of 58.7m @ 6.5g/t Au & 0.1% Cu (381.6 gram-metres Au (gm)
(3)) from 1,754m includes 37m @ 9.98g/t Au & 0.14% Cu from 1,754m, which
approximates to the LLU with the massive sulphide identified in the core.
These assays are considered to be dominantly stratabound and were intersected
by the drill hole at a high angle to bedding, making them close to true width
intersections of the mineralisation.
A further intercept of 34.1m @ 1.1g/t Au (37.5 gm Au) from 1,820m extends
below the LLU, within the lower interpreted vertical stockwork corridor, and
weak mineralisation extends further to the end of hole.
While this result indicates the extension of the structure and geology from
the WDU to the Pinnacles prospect, further drilling will be required to
confirm the existence and tenor of mineralisation between the two zones.
Note 3: Formula: gm = interval width multiplied by Au grade.
Figure 4: Pinnacles drilling location with respect to existing WDU resource
and underground infrastructure - isometric view looking NNW.
Figure 5: Pinnacles hole WRC15403A showing intercepts and Telfer shaft on
interpreted geology with LLU in orange (200m+/- clip).
Proximity to existing underground infrastructure
The Main Dome Underground (MDU) is situated below the Main Dome Open Pit, and
to date has mined over 75Mt of ore, for more than 3.1Moz gold and 210kt
copper.
The MDU crusher and hoist to surface is located at a depth of approximately
1,000m below surface and is approximately 1.5km north-east of the Pinnacles
mineralisation, which is similar to the distance between the current WDU
resource and the crusher and hoist (Figure 4).
The underground crusher and hoist provide an efficient and low-cost materials
handling system that transports ore from the underground crusher to surface
and is then directly conveyed into train 1 of the Telfer processing plant.
This underground materials handling system has a capacity of approximately
6Mtpa and has been in continuous use since its completion in 2007.
Currently the Main Dome Underground is operating at a mining rate of
approximately 1.2Mtpa. Accordingly, there is significant latent infrastructure
capacity at the MDU to support potential mining operations at WDU, including:
· ~6Mtpa crushing and hoist haulage capacity via the existing
shaft;
· water pumping infrastructure with installed capacity of 132L/s,
with current mining activities in the MDU utilising on average 50L/s;
· ventilation infrastructure designed for approximately 5Mtpa SLC,
currently operating as a ~1.2Mtpa stoping operations;
· electricity generation from the Telfer power plant and
transmission via the MDU; and
· a paste plant.
Next steps
Planning is underway to complete at least three wedges off hole WRC14503A with
the aim of gaining 50-100m of separation of intercepts along strike both north
and south (Mine Grid) and down dip within the LLU massive sulphide.
Further surface drilling to infill the 1.2km strike length between Pinnacles
and the current WDU resource, to confirm the existence and tenor of
mineralisation between these zones and potentially enable extension of the WDU
resource, is also being considered, as is the potential for an underground
drill out of this zone.
This announcement is approved for release by Shaun Day, Greatland's Managing
Director.
Contact
For further information, please contact:
Greatland Resources Limited
Shaun Day, Managing Director | Andrew Bowler, Head of Investor Relations
info@greatland.com.au (mailto:info@greatland.com.au)
Nominated Advisor
SPARK Advisory Partners
Andrew Emmott / James Keeshan / Neil Baldwin | +44 203 368 3550
Corporate Brokers
Canaccord Genuity | James Asensio / George Grainger | +44 207 523 8000
RBC Capital Markets | James Agnew / Jamil Miah | Scott Redwood |
+44 207 029 0528
Media Relations
Australia - Fivemark Partners | Michael Vaughan | +61 422 602 720
About Greatland
Greatland is a gold and copper mining company listed on the Australian
Securities Exchange and London Stock Exchange's AIM Market (AIM:GGP, ASX:GGP),
and operates its business from Western Australia.
The Greatland portfolio includes the 100% owned Telfer mine, the adjacent 100%
owned brownfield world-class Havieron gold-copper development project, and a
significant exploration portfolio within the surrounding region. The
combination of Telfer and Havieron provides for a substantial and long-life
gold-copper operation in the Paterson Province in the East Pilbara region of
Western Australia.
Forward-Looking Statements
This document includes forward-looking statements and forward-looking
information within the meaning of securities laws of applicable jurisdictions.
Forward-looking statements can generally be identified by the use of words
such as "may", "will", "expect", "intend", "plan", "estimate", "anticipate",
"believe", "continue", "objectives", "targets", "outlook" and "guidance", or
other similar words and may include, without limitation, statements regarding
estimated reserves and resources, certain plans, strategies, aspirations and
objectives of management, anticipated production, study or construction dates,
expected costs, cash flow or production outputs and anticipated productive
lives of projects and mines.
These forward-looking statements involve known and unknown risks,
uncertainties and other factors that may cause actual results, performance and
achievements or industry results to differ materially from any future results,
performance or achievements, or industry results, expressed or implied by
these forward-looking statements. Relevant factors may include, but are not
limited to, changes in commodity prices, foreign exchange fluctuations and
general economic conditions, increased costs and demand for production inputs,
the speculative nature of exploration and project development, including the
risks of obtaining necessary licences and permits and diminishing quantities
or grades of reserves, political and social risks, changes to the regulatory
framework within which Greatland operates or may in the future operate,
environmental conditions including extreme weather conditions, recruitment and
retention of personnel, industrial relations issues and litigation.
Forward-looking statements are based on assumptions as to the financial,
market, regulatory and other relevant environments that will exist and affect
Greatland's business and operations in the future. Greatland does not give any
assurance that the assumptions will prove to be correct. There may be other
factors that could cause actual results or events not to be as anticipated,
and many events are beyond the reasonable control of Greatland.
Forward-looking statements in this document speak only at the date of issue.
Greatland does not undertake any obligation to update or revise any of the
forward-looking statements or to advise of any change in assumptions on which
any such statement is based.
Competent Persons Statement
Information in this announcement pertaining to exploration results is based
on, and fairly represents, information and supporting documentation compiled
by and approved by Mr Damien Stephens, a Member of the Australian Institute
of Mining and Metallurgy (AusIMM), who has more than 30 years relevant
industry experience. Mr Stephens, an employee of the Company, has sufficient
experience relevant to the style of mineralisation, type of deposit under
consideration, and to the activity which he is undertaking to qualify as a
Competent Person as defined by the 2012 Edition of the Australasian Code for
Reporting of Exploration Results, Mineral Resources and Ore Reserves (the JORC
Code) and under the AIM Rules - Note for Mining and Oil & Gas Companies,
which outline standards of disclosure for mineral projects. Mr
Stephens consents to the inclusion in this announcement of the exploration
results and the supporting information in the form and context in which they
are presented.
This announcement contains references to Mineral Resource estimates for
Telfer, which have been extracted from the Company's ASX announcement dated 30
March 2026 titled 'December 2025 Group Mineral Resource Statement'. The
Company confirms that it is not aware of any new information or data that
materially affects the information included in those announcements, and in the
case of the estimates of Mineral Resource and Ore Reserve, that all material
assumptions and technical parameters underpinning each of the estimates in the
relevant ASX announcement continue to apply and have not materially changed.
Drillhole Data and Au-Cu Significant Intersections
Significant assay intercepts are reported as length-weighted averages in Table
1 and Table 2. Intervals less than 10 Au gram metres and those with <1 g/t
Au average grade have not been included.
All Telfer exploration primary intervals are calculated at 0.2g/t Au cut-off
and minimum 0.1m downhole width with 5m maximum consecutive internal dilution.
Table 1: Significant intercepts & drilling data (Telfer Mine Grid).
HOLEID EAST NORTH RL Depth Dip Azimuth From To Width Au ppm Cu pct Au (GM)
(m)
WRC14503A 57682 11454 5498 1858.2 -84.9 80 1721 1731.4 10.4 2.09 0.02 21.6
1735.6 1745 9.4 1.43 0.04 13.4
1754 1812.7 58.7 6.5 0.10 381.6
1820 1854.1 34.1 1.1 0.04 37.5
Table 2: Historical intercepts & drilling data (Telfer Mine Grid).
HOLEID EAST NORTH RL depth Dip Azimuth (grid) from to Width (m) Au ppm Cu pct Au (gm)
WRC14502 57690 11453 5498 1500 -85 85 No significant intercepts
WRC17902 58415 11790 5506 1788 -74 346 387 398 11 0.27 0.01 13
717.57 734 16.4 16.66 0.015 18
772 776.05 4 14.88 0.003 21
835 851 16 0.21 0.071 19
1376.85 1378.1 1.3 46.7 0.034 25
1439 1444 5 3.73 0.045 20
1539 1550 11 0.64 0.059 12
WRC25046 58182 12509 5520 1608 -85 85 1172 1202 30 1.77 0.231 67
1313.75 1324.5 10.8 3.12 0.127 12
JORC 2012 Table 1: Section 1 - Sampling Techniques and Data
Criteria Commentary
Sampling techniques All current samples are obtained from diamond drilling.
Diamond core (PQ-HQ and NQ) was cut using an automated core saw and sampled as
half core.
Predominately 1m samples were obtained, but lengths range from 0.2 metre to
1.2 metre if adjusted to geological or major alteration boundaries. All
available drill core was sampled.
Drilling techniques Diamond core drilling was from surface with PQ3, HQ3 and NQ2 diameter coring
configuration and from RC pre-collars, generally starting with HQ3 and ending
in NQ2.
Core from drill holes is orientated on 1.5m, 3m and 6m runs using an Axis
CHAMP ORI™ orientation tool. At the end of each run, the bottom of hole
position is marked by the driller, which is later transferred to the whole
drill run core run length with a bottom hole reference line.
Drill sample recovery Core recovery is systematically recorded from the commencement of coring to
end of hole by reconciling against drillers depth blocks in each core tray
with data recorded in the database. Driller's depth blocks provided the depth,
interval of core recovered, and interval of core drilled.
Core recoveries were 95 - 100%.
Logging All core samples were geologically logged by geologists and are considered to
have been logged in appropriate detail to support Mineral Resource estimation,
mining studies and metallurgical studies. Basic geotechnical logging of RQD
was completed by field technicians or geologists.
Core logs were qualitative and quantitative in nature. Lithology and
alteration were logged qualitatively; mineralisation, veining, structure and
geotechnical data (RQD) were logged quantitatively. Core was photographed both
dry and wet after metre marking and orientation.
100% of all recovered core were logged in the targeted stratigraphy.
Magnetic susceptibility, sometimes with conductivity measurements were
recorded every metre using a KT20 or KT10 machine. Bulk density of selected
drill core intervals was determined at site on whole core samples using the
Archimedes method.
Logging information was digitally recorded and validated prior to import into
an acQuire database.
Sub-sampling techniques and sample preparation All sampled core was cut with an automatic core saw in a consistent way that
preserved the bottom of hole reference line, where present. Half core was used
for normal sampling and quarter core for field duplicates. Samples were
collected in pre-numbered calico bags mostly 1 metre in length, but also
ranged from 0.2m to 1.5m. Sample weights typically varied from 0.5kg to 7kg.
Sample sizes are considered appropriate for the style of mineralisation.
Assaying quality control procedures consisted of the inclusion of certified
reference material (CRM) and blank samples at an insertion rate of 1:20 and
1:40 respectively. Duplicate samples were collected from crush and pulp
samples at a rate of 1:20.
Samples were prepared at the Telfer Laboratory or freighted by road to
Intertek Laboratory, Perth (Intertek).
Samples were dried at 105(o)C, and the bulk of the samples pulverised (using
LM5) to produce a pulped product with minimum standard of 95% passing 106µm.
Oversize primary samples were crushed and a 3kg subsample then milled with the
LM5 mill. Routine grind size analysis is conducted.
Quality of assay data and Laboratory tests Assaying of drill core samples was conducted at Intertek. All samples were
assayed for 48 elements using a 4-acid digestion followed by ICP+MS/OES
finish. MS determination (method 4A/MS907), which is considered to provide a
total assay for copper.
Gold analyses were determined by 50g fire assay with AAS finish (method
FA50N/AA), which is considered to provide a total assay for gold.
Sampling and assaying quality control procedures consisted of inclusion of
certified reference material (CRMs), coarse residue and pulp duplicates with
each batch (at least 1:20). Assays of quality control samples were compared
with reference samples in the database and verified as acceptable prior to use
of data from analysed batches.
Laboratory quality control data, including laboratory standards, blanks,
duplicates, repeats and grind size results are captured in the SQL databases
and assessed for accuracy and precision for recent data.
Analysis of the available quality control sample assay results indicates that
an acceptable level of accuracy and precision has been achieved and the
database contains no analytical data that has been numerically manipulated.
The assaying techniques and quality control protocols used are considered
appropriate for the data to be used for reporting exploration drilling
results.
Verification of sampling and assaying Sampling intervals defined by the geologist are electronically assigned sample
identification numbers prior to core cutting. Corresponding sample numbers
matching pre-labelled calico bags are assigned to each interval.
All sampling and assay information were stored in a secure database with
restricted access.
Electronically generated sample submission forms providing the sample
identification number accompany each submission to the laboratory. Assay
results from the laboratory with corresponding sample identification are
loaded directly into the database.
No twinned holes have been completed.
There are no currently known drilling, sampling, recovery, or other factors
that could materially affect the accuracy or reliability of the data.
Location of data points Drill collar locations were surveyed using a differential Trimble R10
differential GPS with RTK with a stated accuracy of +/- 0.01m accuracy or
handheld Garmin 67/66i GPS with an accuracy of +/- 5m.
Drill rig alignment was attained using a REFLEX TN14 GYROCOMPASS™. Downhole
survey was collected every 6m and 30m using a Reflex OMNIx™42 north seeking
gyro tool.
Mining operations at Telfer Gold Mine adhere to periodic reporting
requirements for the WA Department of Mines, Industry Regulation and Safety
(DMIRS), using the MGA94/AHD coordinate system for official submissions.
However, site operations utilise the Telfer Mine Grid (TMG) and Telfer Height
Datum (THD), requiring coordinate transformations between the national and
operational coordinate systems.
This has been supplied by AAM Surveys in 1995 (AMG84 to Telfer Mine Grid) and
AAMHATCH in February 2007 (Telfer Mine Grid to MGA Transformation). Both
reports also addressed the height datum and in 2007 established the THD=AHD +
5193.7m. A local grid covers the whole of the Telfer mine area (Telfer Mine
Grid 2002). It is oriented with grid north at 44o03'12' west of magnetic north
All collar coordinates are provided in the Telfer Mine Grid 2002
Data spacing and distribution Individual holes are targeting specific targets, and are not part of a grid
pattern, all holes are orientated at approximately 90 degrees to the
interpretation geological strike of the intended target.
Orientation of data in relation to geological structure Diamond holes are orientated perpendicular to the interpreted strike of the
target. The hole was angled at 85⁰ from surface to intersect the moderate to
steeply dipping sandstone and siltstone stratigraphy, reef and stock work
mineralisation at a high angle.
Sample security The security of samples is controlled by tracking samples from drill rig to
database.
Drill core was generally delivered from the drill rig to the Telfer core yard
every shift.
Samples were either prepped at the onsite laboratory and flown to Intertek in
Perth or freighted in sealed bags, labelled by bar codes, by road to the
Laboratory by an authorised freight company.
All samples are collected in pre-numbered calico bags. Verification of sample
numbers and identification is conducted by the laboratory on receipt of
samples, and sample receipt advise issued to Greatland.
Details of all sample movement are recorded in a database table. Dates, Hole
ID sample ranges, and the analytical suite requested are recorded with the
dispatch of samples to analytical services. Any discrepancies logged at the
receipt of samples into the analytical services are validated.
Audits or reviews No audits for reviews have been completed.
JORC 2012 Table 1: Section 2- Reporting of Exploration Results
Criteria Commentary
Mineral tenement and land tenure status The Pinnacles Prospect is located on M 45/7 which is 100% owned by Greatland
Pty Ltd,
An Indigenous Land Use Agreement (ILUA) has been in place since December 2015,
covering all operational aspects of the site. Telfer operations also remain
compliant with the Mining Rehabilitation Fund (MRF) levy.
The Telfer district was first geologically mapped by the Bureau of Mineral
Resources in 1959, though no gold or copper mineralization was identified. In
1971, regional sampling by Day Dawn Minerals NL detected anomalous copper and
gold at Main Dome. From 1972 to 1975, Newmont Pty Ltd conducted extensive
exploration and drilling, defining an open pit reserve primarily in the Middle
Vale Reef. In 1975, BHP Gold acquired a 30% stake in the project, and in 1990,
Newmont and BHP Gold merged their Australian assets to form Newcrest Mining
Limited. Newcrest managed exploration and resource drilling from 1990 until
its acquisition by Newmont Corp on November 6, 2023. Newmont later divested
Telfer, selling it to Greatland Gold on December 4, 2024, which now oversees
exploration and drilling activities.
No previous drilling at Pinnacles targeting the LLU horizon has been
undertaken. The nearest hole intersecting the LLU was collared >800m to the
north.
Exploration done by other parties Newcrest and Newmont have completed multiple phases of drilling since the
discovery of the Telfer mine to aid in the resource development. This work
identified mineralisaton within the LLU at what has now been defined as the
West Dome Undergound resource by Greatland. This resource sits 1.2km to grid
north of the Pinnacles intersection.
This drilling including the Greatland subsequent drillout provides a strong
framework for the geological and structural interpretation of the Telfer host
rock sequence, which was used to target the pinnacles hole.
There is a single drilling intersection of the targeted Lower Limey Unit in
hole WRC17902 on the eastern limb of the WDU antiform approximately 730m to
grid north of the Pinnacles hole which, while showing mineralisation did not
intersect the target hinge zone. There is no other drill testing of the LLU
south of this hole along the West Dome / Pinnacles trend.
Geology Telfer is located within the northwestern Paterson Orogen and is hosted by the
Yeneena Supergroup, a 9 km thick sequence of marine sedimentary rocks. Gold
and copper mineralization occurs in stratiform reefs and stockworks within the
Malu Formation of the Lamil Group, controlled by both structure and lithology.
Mineralisation styles include high-grade narrow reefs, reef stockwork
corridors, sheeted vein sets, and extensive low-grade stockwork, which forms
most of the sulphide resource.
Sulphide mineralisation at Telfer consists mainly of pyrite and chalcopyrite,
with copper minerals including chalcopyrite, chalcocite, and bornite. Gold is
primarily free-grained or associated with sulphides and quartz/dolomite
gangue, with a correlation between vein density and gold grade. The highest
gold and copper grades occur within bedding sub-parallel reef systems,
including multiple reef structures in Main Dome and West Dome, such as
E-Reefs, MVR, M10-M70 reefs, A-Reef, B-Reefs (notably B30) and the LLU.
Additional mineralisation occurs in northwest-trending and north-dipping
veins. Stockwork mineralisation, found in open pits, Telfer Deeps the Vertical
Stockwork Corridor (VSC) and the Western stockwork corridor (WSC), is best
developed in the axial zones of Main Dome and West Dome, often extending over
large areas (0.1 km to 1.5 km). It can include brecciated zones filled with
quartz, carbonate, and sulphides.
Drill hole information Refer to Table 1 and Table 2 - Significant Intercepts.
Data aggregation methods Significant assay intercepts are reported as length-weighted averages in Table
1 and Table 2. Intervals less than 10 Au gram metres and those with <1 g/t
Au average grade have not been included.
All Telfer exploration primary intervals are calculated at 0.2g/t Au cut-off
and minimum 0.1m downhole width with 5m maximum consecutive internal dilution.
No top cuts are applied to intercept calculations.
Relationship between mineralisation widths and intercept lengths Drill holes were angled to intersect steeply to moderately dipping geological
targets at high angles.
All significant assay intervals are down hole widths as the true orientation
of mineralisation is currently unknown.
Diagrams As provided.
Balanced reporting The report is considered balanced.
Other substantive exploration data See body of announcement and figures.
Further work Further work is required at Pinnacles including additional wedge and extension
holes.
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