First Drill Assays Confirm High-Grade Manganese at Kuro
Released
Released
Announcement PDF
Registered Offices – Trek Metals Limited – ARBN 124 462 826
Australia
Suite 5/2 Centro Avenue
Subiaco Western
Australia 6008
Bermuda
Vallis Building, 4th Floor
58 Par-la-Ville Road
Hamilton HM 11
Postal
PO Box 1696
Subiaco
WA 6904
Phone
08 6383 7844
Email
info@trekmetals.com.au
6 August 2026
First Drill Assays Confirm High-Grade Manganese at Kuro
Multiple high-grade intercepts including 10m @ 42% Mn returned in the first batch of laboratory
assays, confirming the discovery of an extensive, near-surface manganese system
Highlights
• Maiden drill assays confirm a high-grade, near-surface manganese discovery at Kuro.
• Standout intercept of 10m @ 42.3% Mn from 13m in 26XCRC020, within:
o 13m @ 34.9% Mn from 13m
• Multiple additional high-grade results include:
o 4m @ 44.6% Mn from surface in 26XCRC007
o 11m @ 24.0% Mn from 6m in 26XCRC018, including:
2m @ 31.8% Mn from 7m; and
4m @ 32.3% Mn from 12m
o 13m @ 19.9% Mn from 24m in 26XCRC015, including:
7m @ 28.8% Mn from 26m
o 11m @ 19.3% Mn from 9m in 26XCRC014, including:
3m @ 32.7% Mn from 9m
o 8m @ 25.4% Mn from 8m in 26XCRC016, including:
5m @ 32.8% Mn from 8m
• Peak assay of 54.4% Mn (70.3% MnO) from 16m down-hole in 26XCRC020, highlighting that
high-grade manganese mineralisation occurs at depth in drilling, not only in surface samples.
• 15 of the 21 holes reported to date intersected manganese above a 5% Mn cut-off.
• Samples grading ≥20% Mn average 2.7% Fe and 0.04% P for an Mn:Fe ratio of 13:1, rising to 47:1
in the highest-grade intercept (10m @ 42.3% Mn in 26XCRC020, at 0.90% Fe).
• Remaining assay results from the rest of the Phase 1 drilling expected over the next 3-5 weeks.
• Induced Polarisation (IP) geophysical surveying – confirmed as a proven targeting tool to locate
concealed high-grade manganese beneath cover at Kuro – is continuing across high-priority
areas within the interpreted prospective basin.
• Further earthmoving has commenced at Kuro ahead of upcoming drilling, while the RC drill rig
continues to test regional targets before returning to Kuro.
Trek Metals Limited (ASX: TKM) (“Trek” or the “Company”) is pleased to advise that the first batch of
assay results from the maiden Reverse Circulation (RC) drill program at the Kuro manganese discovery,
within the 100%-owned Christmas Creek Project in Western Australia, have confirmed Kuro as a
significant near-surface, high-grade manganese discovery.
2
Laboratory assays for the first 21 RC holes have confirmed the presence of an extensive high-grade,
near-surface manganese system, with 10 holes returning grades above 20% Mn and 15 of the 21
returning intervals above a 5% Mn cut-off.
The best result was returned from drill-hole 26XCRC020, which intersected 13m @ 34.9% Mn from
13m, including 10m at 42.3% Mn from 13m with a peak one-metre assay of 54.4% Mn. Hole
26XCRC007 returned another very high-grade interval of 4m @ 44.6% Mn from surface. Significant
intercepts are reported in Table 1 and Figures 1-4 below.
Table 1. Significant intercept table of laboratory assays for holes 26XCRC001 – 26XCRC021, using a 5% Mn lower cut-off for
broad intercepts and a 20% Mn lower cut-off for high-grade sub-intervals (including) with a maximum internal dilution of
2m. Widths reported are downhole as true widths are not known. Manganese (Mn) Metres are Width (m) x Mn%.
Hole ID
From
(m)
To
(m)
Width
(m)
Mn (%)
Mn Metres
(m x %)
Significant Intercept
26XCRC002 11 12 1 8.60 8.60 1m @ 8.6% Mn from 11m in 26XCRC002
26XCRC004 5 7 2 12.83 25.65 2m @ 12.8% Mn from 5m in 26XCRC004
26XCRC006 0 15 15 13.16 197.34
15m @ 13.2% Mn from 0m in 26XCRC006, including
3m @ 29.6% Mn from 2m
26XCRC007 0 4 4 44.62 178.49 4m @ 44.6% Mn from 0m in 26XCRC007
26XCRC008 0 1 1 7.92 7.92 1m @ 7.9% Mn from 0m in 26XCRC008
26XCRC008 4 5 1 6.93 6.93 1m @ 6.9% Mn from 4m in 26XCRC008
26XCRC009 7 8 1 11.94 11.94 1m @ 11.9% Mn from 7m in 26XCRC009
26XCRC010 0 1 1 5.58 5.58 1m @ 5.6% Mn from 0m in 26XCRC010
26XCRC011 0 2 2 23.14 46.28
2m @ 23.1% Mn from 0m in 26XCRC011, including
1m @ 28.3% Mn from 0m
26XCRC014 9 20 11 19.34 212.75
11m @ 19.3% Mn from 9m in 26XCRC014, including
3m @ 32.7% Mn from 9m
26XCRC014 23 24 1 7.19 7.19 1m @ 7.2% Mn from 23m in 26XCRC014
26XCRC015 24 37 13 19.93 259.15
13m @ 19.9% Mn from 24m in 26XCRC015, including
7m @ 28.8% Mn from 26m
26XCRC016 8 16 8 25.37 202.93
8m @ 25.4% Mn from 8m in 26XCRC016, including
5m @ 32.8% Mn from 8m
26XCRC017 1 2 1 7.99 7.99 1m @ 8.0% Mn from 1m in 26XCRC017
26XCRC017 9 12 3 17.89 53.66
3m @ 17.9% Mn from 9m in 26XCRC017,
including 1m @ 30.2% Mn from 10m
26XCRC017 16 18 2 11.46 22.93 2m @ 11.5% Mn from 16m in 26XCRC017
26XCRC018 6 17 11 24.00 264.00
11m @ 24.0% Mn from 6m in 26XCRC018, including
2m @ 31.8% Mn from 7m and
4m @ 32.3% Mn from 12m
26XCRC019 0 6 6 25.39 152.32
6m @ 25.4% Mn from 0m in 26XCRC019, including
5m @ 28.1% Mn from 0m
26XCRC019 36 37 1 6.10 6.10 1m @ 6.1% Mn from 36m in 26XCRC019
26XCRC020 13 26 13 34.94 454.28
13m @ 34.9% Mn from 13m in 26XCRC020, including
10m @ 42.3% Mn from 13m
No significant intercepts (no sample >5% Mn): 26XCRC001, 003, 005, 012, 013 & 021.
3
The mineralisation intersected to date is shallow, with all significant intercepts (Table 1 & Figures 1-4)
occurring between surface and 37m down-hole, with the geometry trending from outcrop in the
north-west and progressively getting deeper towards the south-east.
Figure 1. Plan view of Kuro, Gradient Array Induced Polarisation (GAIP) Chargeability anomalism shown as full-colour
background with contour lines (white-red hot indicative of highly chargeable zones), manganese outcrop as grey polygons
with black outlines, completed Reverse Circulation drill-holes with hole ID and total visual massive and semi-massive
manganese intercepts labelled and new (this release) significant laboratory assay results in callouts and coloured dots.
Readers are reminded that Visual estimates of mineral abundance should never be considered a proxy or substitute for
laboratory analyses where concentrations or grades are the factor of principal economic interest. Visual estimates also
potentially provide no information regarding impurities or deleterious physical properties relevant to valuations.
The visually observed manganese mineralisation is not representative of the entire Kuro Prospect, with drilling currently on-
going to further assess the distribution of manganese. Representative drill samples are being routinely collected from the drill
rig and will be analysed at ALS laboratories and reported in due course (laboratory assay results are expected progressively,
with the first batch reported now, the second batch in 2-4 weeks and the final Phase 1 batch in 3-5 weeks).
Trek Metals CEO, Derek Marshall, said:
“Receiving confirmation of high-grade manganese mineralisation below surface in these first
laboratory assays represents a major breakthrough in our ongoing exploration program at Christmas
Creek. Until now we have been working on outcrop rock chip assays and visual estimates in drilling.
While the manganese mineralisation is typically quite visual, having laboratory verification that the
high-grade mineralisation we see at surface does indeed continue below surface is a major milestone
which gives our team the confidence to continue with the next phase of work.
4
“A preliminary review of the geochemistry - noting that these are early drill assays and not metallurgy
- also indicates the potential for a product with low-iron and low-phosphorus in the manganese
mineralised zones, with both iron and phosphorus being the principal penalty elements in manganese
ores. This is very encouraging for the exploration potential for what we consider to be a potentially
large system.
“The thing that I find most encouraging about the Kuro manganese discovery is the regional context.
Kuro is just one prospect area – one that we initially targeted as there was a small window of rocks
sticking out of the ground in a region where most of the rocks are under shallow sand cover. We have
a large, interpreted basin to explore and we are doing just that, with the Moombarriga IP crew
continuing their surveys to identify future drill targets to determine where the RC rig goes next.
“In the meantime, the rig is continuing to test regional targets as we commence earthmoving at the
Coogan copper-gold target and Kuro prior to additional drilling. Two geophysical surveys are also due
to commence shortly, with SAM over the Martin high-grade gold prospect and a regional airborne
magnetic – radiometric survey. We look forward to updating the market with a steady flow of
exploration results and activity as the season progresses.”
Figure 2. Long Section Line 1, along the main (southern) chargeability anomaly along strike from the main manganese
outcrop, showing interpreted geology, highlighting the ~400m strike of visual manganese mineralisation in black. New
laboratory significant intercepts as individual callouts (refer Table 1) and previously released significant visual intercepts
(≥10m of massive to semi-massive manganese) as individual callouts. Cross-section Line 1 location also shown.
Long section line location shown in Figure 1.
Readers are reminded that Visual estimates of mineral abundance should never be considered a proxy or substitute for
laboratory analyses where concentrations or grades are the factor of principal economic interest. Visual estimates also
potentially provide no information regarding impurities or deleterious physical properties relevant to valuations. The visually
observed manganese mineralisation is not representative of the entire Kuro Prospect, with drilling currently on-going to
further assess the distribution of manganese.
5
Representative drill samples are being routinely collected from the drill rig and will be analysed at ALS laboratories and
reported in due course (laboratory assay results are expected progressively, with the first batch reported now, the second
batch in 2-4 weeks and the final Phase 1 batch in 3-5 weeks).
Figure 3. Long Section Line 2, along the northern chargeability anomaly, showing interpreted geology, highlighting the ~300m
and 150m strike of visual manganese mineralisation in black. New laboratory significant intercepts as individual callouts
(refer Table 1) and previously released significant visual intercepts (≥10m of massive to semi-massive manganese) as
individual callouts. Cross-section Line 1 location also shown. Long section line location shown in Figure 1.
Readers are reminded that Visual estimates of mineral abundance should never be considered a proxy or substitute for
laboratory analyses where concentrations or grades are the factor of principal economic interest. Visual estimates also
potentially provide no information regarding impurities or deleterious physical properties relevant to valuations.
The visually observed manganese mineralisation is not representative of the entire Kuro Prospect, with drilling currently on-
going to further assess the distribution of manganese. Representative drill samples are being routinely collected from the drill
rig and will be analysed at ALS laboratories and reported in due course (laboratory assay results are expected progressively,
with the first batch reported now, the second batch in 2-4 weeks and the final Phase 1 batch in 3-5 weeks).
Down-hole continuity within the mineralised zones is good, with the five thickest intercepts
comprising between 8 and 15 contiguous metres above cut-off.
Iron and phosphorus are the principal penalty elements in manganese ore. Samples grading 20% Mn
or better average 2.7% Fe and 0.04% P for an Mn:Fe ratio of approximately 13:1, with manganese and
iron geochemically decoupled and the ratio improving with grade to 47:1 in the 10m @ 42.3% Mn
interval in 26XCRC020, which returned 0.90% Fe. Phosphorus is low across most intercepts but is
elevated in 26XCRC006 and 26XCRC007. Silica is the principal diluent and falls as manganese grade
rises, from 47.5% SiO₂ across the reported intercepts to 24.4% in the highest-grade interval. Lead is
variably distributed, ranging from 49ppm to 0.60% over the reported intercepts, and is lowest in the
highest-grade material. Length-weighted averages for each intercept of 2m or greater are set out in
Table 4. No metallurgical or product characterisation testwork has been undertaken.
6
Figure 4. Cross Section Line linking the two Long Sections (Figure 2 & Figure 3) showing interpreted geology, highlighting the
apparent ~50m widths of visual manganese mineralisation in black of the two pods. New laboratory significant intercepts as
individual callouts (refer Table 1) and previously released significant visual intercepts (≥10m of massive to semi-massive
manganese) as individual callouts. Long-section Line 1 and Line 2 locations also shown. Cross section line location shown in
Figure 1.
Readers are reminded that Visual estimates of mineral abundance should never be considered a proxy or substitute for
laboratory analyses where concentrations or grades are the factor of principal economic interest. Visual estimates also
potentially provide no information regarding impurities or deleterious physical properties relevant to valuations.
The visually observed manganese mineralisation is not representative of the entire Kuro Prospect, with drilling currently on-
going to further assess the distribution of manganese. Representative drill samples are being routinely collected from the drill
rig and will be analysed at ALS laboratories and reported in due course (laboratory assay results are expected progressively,
with the first batch reported now, the second batch in 2-4 weeks and the final Phase 1 batch in 3-5 weeks).
7
Figure 5. Preliminary Merged Residual Gravity imagery showing an interpreted ~16km long prospective Neoproterozoic basin
hosting the Kuro manganese discovery outlined in white, highlighting the interpreted basin boundary and target stratigraphy
within, the existing Kuro IP and drill area in the east and the recently completed gradient array IP extension survey areas.
Notably, all the IP targets are under shallow sand cover with no surface manganese expression. Having
a drill targeting technique that effectively pinpoints significant manganese undercover is therefore
considered to be a pivotal moment for the Company in advancing the Kuro manganese discovery.
The Moombarriga IP crew, which re-mobilised to site on 3 July 2026, has since completed additional
Gradient Array Induced Polarisation (GAIP) surveying surrounding the Kuro Manganese Discovery and
is now continuing this surveying to the north-east of the discovery area in an area that is interpreted
to represent an extension of the basin hosting the manganese mineralisation at Kuro.
8
Authorised by the Board of Directors
ENDS
For further information contact:
INVESTORS: MEDIA:
Derek Marshall Nicholas Read
dmarshall@trekmetals.com.au info@trekmetals.com.au 0419 929 046
JOIN TKM’S INTERACTIVE INVESTOR HUB
https://trekmetals.com.au/auth/signup
Interact with Trek Metal’s announcements and updates by asking
questions and comments which our team can respond to where possible
https://trekmetals.com.au/link/rDvGQy
COMPETENT PERSONS STATEMENT
The information in this report relating to Exploration Results is based on information compiled by the
Company’s Chief Executive Officer, Mr Derek Marshall, a Competent Person, and Member of the
Australian Institute of Geoscientists (AIG). Mr Marshall has sufficient experience relevant to the style
of mineralisation and to the type of activity described 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.” Mr Marshall has disclosed that he holds fully paid Ordinary Shares and
Performance Rights in the Company. Mr Marshall consents to the inclusion in this announcement of
the matters based on his information in the form and content in which it appears.
Cautionary Statement: This announcement reports Exploration Results only. No Mineral Resource
has been estimated for the Kuro Prospect and insufficient exploration has been completed to
estimate a Mineral Resource. Further drilling and evaluation is required, and it is uncertain whether
further exploration will result in the estimation of a Mineral Resource.
DISCLAIMERS AND FORWARD-LOOKING STATEMENTS
This announcement contains forward looking statements. Forward looking statements are often, but
not always, identified by words such as "seek", “target”, "anticipate", “forecast”, "believe", "plan",
"estimate", "expect" and "intend" and statements that an event or result "may", "will", "should",
"could" or "might" occur or be achieved and other similar expressions.
The forward-looking statements in this announcement are based on current expectations, estimates,
forecasts and projections about Trek and the industry in which it operates. They do, however, relate
to future matters and are subject to various inherent risks and uncertainties. Actual events or results
may differ materially from the events or results expressed or implied by any forward-looking
statements. The past performance of Trek is no guarantee of future performance.
None of Trek’s directors, officers, employees, agents or contractors makes any representation or
warranty (either express or implied) as to the accuracy or likelihood of fulfilment of any forward-
looking statement, or any events or results expressed or implied in any forward-looking statement,
except to the extent required by law. You are cautioned not to place undue reliance on any forward-
looking statement. The forward-looking statements in this announcement reflect views held only as
at the date of this announcement.
9
Table 2. Specific Exploration results referred to in this report were originally reported in the following Company
announcements.
Title Date
IP Drilling Validates Concealed Manganese Targeting at Kuro
https://trekmetals.com.au/announcements/7646589
23 July 2026
Drilling Continues to Intersect Mineralisation at Kuro
https://trekmetals.com.au/announcements/7618301
6 July 2026
Multiple Mineralised Zones Intersected at Kuro
https://trekmetals.com.au/announcements/7604907
29 June 2026
Kuro IP Survey planned, RC Drill contract and assay results
https://trekmetals.com.au/announcements/7467887
30 March 2026
Petrophysics Confirms Geophysical Response from Kuro Rock Chips, IP Survey
Planned and RC Drill Contract Awarded
https://trekmetals.com.au/announcements/7457333
23 March 2026
Outstanding New High-Grade Manganese Rock Chip Results at the Kuro Prospect -
Christmas Creek Project, WA
https://trekmetals.com.au/announcements/7326226
19 January 2026
High-Grade Manganese Discovery at Christmas Creek Strengthened by Extensive,
Strong Gravity Anomalies
https://trekmetals.com.au/announcements/7311646
15 December 2025
Trek to accelerate exploration at new High-Grade Manganese Discovery at
Christmas Creek Project, WA
https://trekmetals.com.au/announcements/7263873
17 November 2025
Exceptionally High-Grade Manganese Discovery at Christmas Creek Project, WA
https://trekmetals.com.au/announcements/7259499
13 November 2025
Discovery focused drilling gains momentum on several fronts
https://trekmetals.com.au/announcements/7075982
29 July 2025
The Company confirms that it is not aware of any new information or data that materially affects the information
included in the original announcements and that all material assumptions and technical parameters
underpinning the exploration results continue to apply and have not materially changed.
10
Table 3. Collar Table relating to holes which samples comprised Batch 1 being reported from 2026 Reverse Circulation
drilling at the Christmas Creek Project, listing holes 26XCRC001 – 26XCRC021, co-ordinates listed are grid MGA2020 Z52.
Hole ID Type Depth North East RL Dip Azi Lease ID Prospect
26XCRC001 RC 84 7874448 266964 337 -60 35 E80/4975 Kuro
26XCRC002 RC 54 7874483 266996 335 -60 35 E80/4975 Kuro
26XCRC003 RC 150 7874185 266731 334 -60 35 E80/5427 Kuro
26XCRC004 RC 100 7874229 266752 335 -60 35 E80/5427 Kuro
26XCRC005 RC 150 7874160 266696 334 -60 35 E80/5427 Kuro
26XCRC006 RC 48 7874337 266601 338 -65 229 E80/5427 Kuro
26XCRC007 RC 30 7874234 266662 333 -90 0 E80/5427 Kuro
26XCRC008 RC 40 7874339 266711 336 -90 0 E80/5427 Kuro
26XCRC009 RC 78 7874006 267025 329 -90 0 E80/4975 Kuro
26XCRC010 RC 60 7874074 266740 330 -90 0 E80/5427 Kuro
26XCRC011 RC 60 7874538 266909 337 -80 200 E80/5427 Kuro
26XCRC012 RC 84 7874511 266895 338 -90 0 E80/5427 Kuro
26XCRC013 RC 100 7874418 266838 334 -90 0 E80/5427 Kuro
26XCRC014 RC 54 7873887 267248 330 -90 0 E80/4975 Kuro
26XCRC015 RC 72 7873972 267353 329 -90 0 E80/4975 Kuro
26XCRC016 RC 72 7874194 267264 337 -90 0 E80/4975 Kuro
26XCRC017 RC 60 7874328 267222 337 -90 0 E80/4975 Kuro
26XCRC018 RC 72 7874051 267117 332 -90 0 E80/4975 Kuro
26XCRC019 RC 60 7873976 267052 331 -90 0 E80/4975 Kuro
26XCRC020 RC 72 7873964 267181 332 -90 0 E80/4975 Kuro
26XCRC021 RC 48 7873808 267312 332 -90 0 E80/4975 Kuro
11
Table 4. Length-weighted average composition of the significant intercepts reported in Table 1. Broad intercepts are
calculated using a 5% Mn lower cut-off and high-grade “including” sub-intervals using a 20% Mn lower cut-off, each with a
maximum internal dilution of 2m. Sub-intervals are contained within the broad intercept immediately above and are not
additional to it; the weighted average row relates to the broad intercepts only. Broad intercepts of less than 2m downhole
width are excluded from this table. Fe and P are reported as the element, converted from Fe₂O₃ and P₂O₅ respectively. Mn:Fe
is the ratio of elemental manganese to elemental iron. LOI is loss on ignition. Sulphur is below 0.02% S across all reported
intercepts and is not tabulated; combined K₂O + Na₂O averages 1.4% and CaO + MgO averages 0.4%. All results are reported
on an as-received basis. Iron and phosphorus are the principal penalty elements in manganese ore; lead, arsenic, silica,
alumina and barium are reported as constituents relevant to any future assessment of the mineralisation. No metallurgical
or product characterisation testwork has been undertaken and no inference as to product specification should be drawn from
these results.
Hole ID
From
(m)
Width
(m)
Mn % Fe % Mn:Fe P % SiO₂ % Al₂O₃ % BaO % LOI % Pb ppm As ppm
26XCRC004 5 2 12.8 6.74 1.9 0.022 58.4 6.44 0.34 6.0 636 28
26XCRC006 0 15 13.2 6.27 2.1 0.105 57.5 6.05 0.61 6.1 801 15
including 2 3 29.6 8.25 3.6 0.177 28.0 5.36 1.08 10.0 2,343 38
26XCRC007 0 4 44.6 1.86 24 0.115 13.5 5.19 1.37 11.9 49 18
26XCRC011 0 2 23.1 3.14 7.4 0.050 47.2 5.74 1.66 7.1 432 14
including 0 1 28.3 3.09 9.2 0.065 39.5 5.04 2.22 7.9 521 17
26XCRC014 9 11 19.3 1.72 11 0.023 53.2 6.40 2.00 6.1 91 20
including 9 3 32.7 1.67 20 0.032 34.6 4.99 1.89 8.6 125 26
26XCRC015 24 13 19.9 2.97 6.7 0.026 53.9 5.43 0.53 5.5 381 29
including 26 7 28.8 1.87 15 0.016 42.8 4.74 0.48 7.0 604 39
26XCRC016 8 8 25.4 4.44 5.7 0.016 44.0 5.03 0.45 7.3 1,834 31
including 8 5 32.8 5.48 6.0 0.017 31.8 4.04 0.45 8.6 2,711 38
26XCRC017 9 3 17.9 6.57 2.7 0.023 48.3 5.31 0.30 7.8 5,960 27
including 10 1 30.2 4.15 7.3 0.017 29.8 3.89 0.19 11.3 11,450 34
26XCRC017 16 2 11.5 11.61 1.0 0.039 52.6 5.82 0.24 6.4 209 20
26XCRC018 6 11 24.0 1.89 13 0.016 50.5 4.69 0.75 6.7 755 20
including 7 2 31.8 1.11 29 0.015 39.2 4.19 1.00 8.1 1,120 18
including 12 4 32.3 2.00 16 0.017 38.5 3.91 0.64 8.1 729 28
26XCRC019 0 6 25.4 3.15 8.1 0.016 44.2 6.16 0.75 8.0 104 19
including 0 5 28.1 3.09 9.1 0.015 40.1 6.27 0.64 8.5 118 20
26XCRC020 13 13 34.9 1.80 19 0.028 33.7 3.57 1.91 8.0 140 26
including 13 10 42.3 0.90 47 0.031 24.4 2.81 2.29 9.3 136 25
Weighted
average
90 23.0 3.56 6.5 0.041 47.5 5.33 1.00 7.0 711 22
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JORC Table Section 1: Sampling Techniques and Data:
Criteria JORC Code explanation Commentary
Sampling
techniques
• Nature and quality of sampling (eg 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 (eg ‘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.
• Drilling was undertaken using RC with a face sampling bit. RC cuttings
were collected at 1m intervals via a cyclone and cone splitter,
producing ~2.5kg (mean 2.42kg and median 2.31kg) samples, with
bulk residues retained on site and composite sampled as 4m intervals.
• All 21 holes were sampled over their full length with 638 one-metre
samples plus 230 four-metre composites, with no composite
exceeding 1% Mn.
• Samples are freighted for analysis at ALS Perth using:
o ME-XRF26s which consists of a Lithium Borate Fusion and X-Ray
Fluorescence Spectroscopy analysis. This method is suitable for
the determination of major and minor elements in ore samples
which require a high dilution digest such as Chromite and high
Manganese ores.
o Fire assay with AAS finish (Au-AA25, 30g), and
o Four-acid digest with ICP-MS (ME-MS61, 48 elements).
These are considered industry-standard and appropriate methods.
• Field duplicates, certified reference materials and blanks were
inserted at a nominal rate of one of each per 50 samples, with
laboratory internal checks also applied. All QA/QC results have been
reviewed and are within acceptable limits — refer to the Quality of
Assay Data and Laboratory Tests section below. Chain of custody
was maintained from site to laboratory.
• All holes completed have been included in figures within the body of
the announcement and all collars relating to holes with new assays in
this announcement are listed in tabular formats in Table 3 & significant
intercepts in Table 1.
• Visual estimates of manganese mineralisation have been estimated
by trained and experienced mineral exploration geologists on the rig
and reviewed by the Competent Person utilising chip tray photos.
Visual estimates included have all been previously released and
readers are referred to announcements listed in Table 2.
The reader is reminded that Visual estimates of mineral abundance
should never be considered a proxy or substitute for laboratory
analyses where concentrations or grades are the factor of principal
economic interest. Visual estimates also potentially provide no
information regarding impurities or deleterious physical properties
relevant to valuations.
The visually observed manganese mineralisation is not representative
of the entire Kuro Prospect, with drilling currently on-going to further
assess the distribution of manganese. Representative drill samples
are being routinely collected from the drill rig and will be analysed at
ALS laboratories and reported in due course (results from the
remaining two batches from Phase 1 are expected in 3-5 weeks).
Drilling
techniques
• Drill type (eg core, reverse circulation, open-
hole hammer, rotary air blast, auger, Bangka,
sonic, etc) and details (eg core diameter, triple
or standard tube, depth of diamond tails, face-
sampling bit or other type, whether core is
oriented and if so, by what method, etc).
• Drill testing was undertaken by Reverse Circulation (RC) with face
sampling drill bit, drill cuttings are returned to surface via inner tubes
in the drill string.
• RC drill cuttings were collected at 1m intervals down the length of each
hole. Sampling was completed from a gated cyclone over a static cone
splitter into a calico bag with an average sample weight of 2.42kg per
1m sample. The remainder of the drill cuttings were collected in green
bags and laid out in rows on a sample pad beside the drill rig.
• Individual 4m samples were then composited from the green bags as
described in a subsequent section. The sampling protocol is common
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Criteria JORC Code explanation Commentary
practice for RC drilling and considered appropriate for the stage of
exploration.
Drill sample
recovery
• 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 preferential
loss/gain of fine/coarse material.
• Reverse Circulation drilling recoveries have been good with
consistency between green bag (and calico split) sizes.
• Duplicate samples were collected from the rig every 50m, with
duplicate pair weights monitored to check the performance of the
cyclone and cone splitter.
• Sample recovery was consistent across the program with the same
drill rig and mostly the same driller operating the drill rig and
maintaining constant drilling conditions with the equipment, including
monitoring bit wear, air return, and cyclone performance.
• A cone splitter was used on the drill rig which theoretically gives an
even and impartial split of the sample when operated correctly.
Adjustable control gates allow the sample size to be calibrated to suit
the ground conditions and target sample size. These measures are
best practice in producing representative samples.
• There is no observed relationship between sample recovery and
observed mineralisation.
Logging • Whether core and chip samples have been
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