High Grade Assays Received for New Lautem Discoveries
Released
Released
Announcement PDF
ASX: ESR
12 February 2025
High Grade Assays Received for New
Lautém Discoveries
HIGHLIGHTS
➔ Ira Miri rock chip samples return assays between 40.0% Mn and 58.6% Mn (Figure 1)
➢ Five rock chip samples were taken from around the discovery area and exported to Australia
➢ The supergene sub-crop in Figure 1 below returned an assay of 58.4% Mn
➢ Boron, phosphorus and silica levels are low
➔ In-situ supergene at the Sica Prospect returned between 46% Mn and 49.3% Mn (Figure 2)
➢ The two rock chip samples were taken from partially outcropping supergene manganese zones
➔ Sica detrital manganese systematically sampled, assays averaged 40.1% Mn (Figure 3)
➢ A further 48 large grab samples taken from the Sica valley floor detrital material to assess the grade
of this material.
➔ Environmental surveys of drill locations on Exploration and Evaluation License MEL2023-CA-ZA001 are
complete and applications to drill are being drafted for the relevant Government bodies.
Figure 1: Estrella MD Chris Daws at the partially outcropping supergene manganese exposure at Ira Miri within
concession MEL2023-CA-ZA001. Lab assays from this outcrop returned a grade of 58.4% Mn
_____________________________________________________________________________________________________________
Office Address London House, Level 8, 216 St Georges Terrace, PERTH WA 6000 Postal Address GPO Box 2517, PERTH WA 6831
Phone +61 8 9481 0389 Fax +61 8 9463 6103
Email info@estrellaresources.com.au
Estrella Resources Limited (ASX: ESR) (Estrella or the Company) is pleased to announce the return of
excellent assays for the two new in-situ supergene manganese discoveries made in its Lautém Manganese
Project in Timor-Leste, along with a bulk determination for the detrital material that has accumulated on the
Sica valley floor.
Figure 2: Estrella CEO Chris Daws at the sub-cropping supergene zone at Sica which returned an assay of 46% Mn (refer
CBR114691)
Figure 3: Example of detrital supergene manganese from the Sica valley floor which averaged 40.1% Mn (Table 2).
The in-situ secondary supergene manganese outcrops at Ira Miri and Sica lie on either side of a river valley
and are around 4.5km apart (Figure 4). The duplication of the Noni Formation, into areas previously thought
to be devoid of the Noni Formation, highlights the predictive capacity of the model and opens up new areas
of prospectivity which the company will now look to capitalise upon.
Figure 4: Location of the Ira Miri and Sica Prospects
Commenting on the new discoveries Estrella Managing Director Chris Daws said:
" I am excited to share the strong progress at our Lautém Manganese Project in Timor-Leste. Recent assays
from the Ira Miri discovery area and the Sica Prospect have confirmed the significant potential for high-grade
manganese mineralisation, reinforcing the value of this project.
We are also pleased with the systematic sampling of detrital material on the Sica valley floor, which further
supports the broader manganese mineralisation across the region. These discoveries have come about
through the development of Estrella’s exploration model which is now being tested and proving highly
successful.
Environmental surveys for drill locations are now complete, and we are in the process of submitting drilling
permit applications to the relevant Government bodies. We are eager to advance the Lautém Manganese
Project and unlock its full potential.”
The Ira Miri (New Water) Manganese Discovery
The outcrop at Ira Miri consists of the top three metres of an in-situ supergene blanket formed within the
Noni Formation. The mineralisation is covered by scree from the overlying limestones, however the trend
can be followed over 4 kilometres within which primary, secondary and tertiary manganese has been
located (Figure 5). Whilst outcrop is limited, the identification of manganese oxide clasts in the scree at the
top of the Noni Formation contact (Figure 5, CBR114685-86) suggests that secondary supergene
mineralisation lies just below the surficial soil cover which is estimated to be only a few meters thick.
Five samples from reconnaissance mapping were exported from Timor-Leste to Australia and submitted to
ALS for geochemistry. The results, presented in Table 1 below, show the Ira Miri secondary supergene
outcrops to be highly enriched in manganese and stripped of deleterious elements (samples CBR114689
and CBR114690). Both the Ira Miri secondary supergene outcrop samples exceeded 58% manganese
(75% MnO) and were very low in boron, phosphorus and silica.
The primary chert (the source rock for the manganese shown in Figure 5 CBR114587) grades up to 20%
Mn. Estrella is exploring for the secondary enrichment zones that have formed on the top of this primary
manganese source, such as the outcrop at Ira Miri. The tertiary manganese occurs as a result of the erosion
of the secondary manganese and detrital deposition into current and historic valley areas. These
accumulations can be significant, such as at Sica, and may well form a supplementary feed to any future
mining operation.
Environmental surveys have been completed in the area to accompany applications that have been
submitted to Timor-Leste’s mineral resources and regulatory body (A.N.M. – Autoridade Nacional dos
Minerais, I.P.) to allow access tracks to be developed ahead of the commencement of drilling. The company
looks forward to the end of the wet season for drilling activities to commence and will begin the community
consultation and education process as soon as possible.
Assays from the rock chip samples (Figure 5) at Iri Miri are presented in Table 1 below.
Figure 5: Sample photographs and locations from the Ira Miri Prospect where primary, secondary and tertiary manganese
has been located over a strike length of 4 km. Estrella is targeting in-situ secondary manganese mineralisation.
Assay results from rock-chip samples are presented in Table 1.
Table 1: Rock chip assays from initial Ira Miri reconnaissance mapping
Sample #
Longitude
Latitude
Description
Mn%
Al2O3%
SiO2%
P2O5%
B ppm
CBR114685
CBR114686
126.90766
126.90768
-8.421499
-8.421498
Tertiary Manganese
Tertiary Manganese
39.96
51.26
1.89
1.05
20.83
8.85
0.13
0.04
10
10
CBR114687
126.90715
-8.421548
Primary Noni Chert
19.64
3.31
37.56
4.62
40
CBR114689
126.91213
-8.424796
Secondary Manganese
58.39
0.61
2.24
0.11
10
CBR114690
126.90968
-8.423507
Secondary Manganese
58.60
0.67
1.61
0.3
10
The Sica Manganese Discovery
The in-situ secondary enrichment at the Sica Prospect was discovered more recently by using the
geological model Estrella has developed. The Sica Valley is the location of a significant accumulation of
tertiary manganese.
The Sica in-situ secondary mineralisation (Figure 2) was sampled and returned assays of 46.0% Mn and
49.3% Mn (CBR114691 and CBR114692 in Table 2). The secondary supergene is a flat oxide layer that is
now being exposed through erosion. The erosion is responsible for concentrating tertiary manganese on
the Sica Valley floor. Another 48 large samples were taken to estimate the tertiary mineralisation grade that
has accumulated in the Sica Valley (Figure 3). The assay results are presented in Table 2.
Table 2: Assay results from the Sica Prospect
Sample #
Longitude
Latitude
Description
Mn%
Al2O3%
SiO2%
P2O5%
B ppm
CBR114691
CBR114692
126.8739289
126.8726578
-8.4092643
-8.4120545
Sica In-situ Secondary
Manganese
45.96
49.26
1.67
1.43
6.76
8.08
0.07
0.07
20
20
CBR114680
CBR114652
CBR114684
CBR114679
CBR114657
CBR114672
CBR114671
CBR114678
CBR114681
CBR114658
CBR114675
CBR114656
CBR114674
CBR114670
CBR114677
CBR114654
CBR114655
CBR114676
CBR114683
CBR114673
CBR114651
CBR114659
CBR114660
CBR114661
CBR114663
CBR114665
CBR114662
CBR114669
CBR114664
CBR114612
CBR114667
CBR114666
CBR114668
CBR114644
CBR114611
CBR114648
CBR114645
CBR114649
CBR114650
CBR114647
CBR114613
CBR114653
CBR114646
CBR114610
CBR114608
CBR114606
CBR114607
CBR114609
126.8711556
126.8711344
126.8712157
126.8712791
126.8714479
126.8715742
126.8715709
126.871244
126.8713225
126.8716286
126.8714328
126.8715295
126.8714098
126.8715965
126.8713737
126.8712675
126.8713115
126.8713525
126.8713154
126.8715087
126.8714381
126.8715927
126.8716017
126.8715334
126.8717301
126.8717238
126.8716824
126.871568
126.8716988
126.8710248
126.8717733
126.8717694
126.8717154
126.8712133
126.8710564
126.8711945
126.8711379
126.8713941
126.8714155
126.8712713
126.8711256
126.8713288
126.8711934
126.8709952
126.8708011
126.8709622
126.8709157
126.8707244
-8.4115466
-8.4116659
-8.4116885
-8.4115802
-8.4115298
-8.4117501
-8.4116464
-8.4115217
-8.411724
-8.4115062
-8.4116498
-8.4115155
-8.411737
-8.4115831
-8.4115929
-8.4114441
-8.4114572
-8.4116195
-8.4117689
-8.4117325
-8.4112951
-8.4113492
-8.4113074
-8.4112625
-8.4113087
-8.4112917
-8.4112482
-8.4112573
-8.4113301
-8.41128
-8.4112194
-8.4112817
-8.4111957
-8.4111916
-8.4111781
-8.4113523
-8.41127
-8.4113955
-8.4113043
-8.4113175
-8.4111765
-8.411402
-8.4112687
-8.4110633
-8.4108702
-8.4108173
-8.4107704
-8.4110037
57.06
56.66
54.56
54.36
54.10
53.54
53.39
53.14
53.01
52.94
52.76
52.20
52.03
51.84
51.80
49.59
48.66
47.25
46.48
46.24
45.67
44.56
44.28
43.47
43.34
42.67
42.04
37.04
36.49
36.33
34.77
34.40
33.57
33.19
32.64
28.57
27.23
27.15
26.91
26.50
26.37
24.03
23.69
17.43
12.45
9.91
8.61
1.19
0.9
1.03
0.98
0.92
1.29
1.09
0.96
1.04
0.96
1.19
1.16
0.88
1.22
1.26
1.23
1.52
1.8
1.49
1.91
1.53
2.22
1.95
2.02
2.31
2.12
2.21
2.39
2.99
2.84
2.9
2.88
3.03
2.49
2.89
3.45
4.08
2.65
3.21
3.64
3.07
4
4
3.01
2.91
2.62
2.49
3.25
3.41
3.45
3.36
3.78
5.68
4.66
3.8
4.94
4.61
4.5
6.65
4.02
4.15
5.34
4.92
6.44
8.16
6.75
6.52
5.53
7.95
7.16
8.84
9.68
9.83
10.92
10.46
13.78
13.19
19.04
19.54
21.63
8.17
14.54
15.2
20.22
10.34
10.36
15.73
13.81
18.58
16.89
10.16
8.08
7.38
7.51
LNR
0.07
0.21
0.09
0.08
0.1
0.1
0.06
0.1
0.12
0.31
0.09
0.07
0.12
0.13
0.08
0.1
0.26
0.23
0.06
0.09
0.08
0.05
0.06
0.08
0.04
0.05
0.4
0.38
0.28
0.42
0.2
0.55
0.34
0.18
0.41
0.17
0.23
0.14
0.1
0.18
0.38
0.19
0.17
9.89
14.3
13.86
15.09
10
10
10
20
10
10
20
10
10
20
10
10
10
20
20
20
20
20
20
20
30
30
30
30
30
30
30
40
40
30
40
40
40
30
30
40
40
30
40
40
30
40
40
40
40
40
40
Sica valley tertiary Mn
The average grade of the Sica Valley tertiary mineralisation is 40.1% Mn. There is an inverse relationship
between manganese and silica, phosphorus and iron. This reflects the difference in mineralogy within the
supergene process where manganese is progressively stripped from the source cherts (high in silica,
phosphorus and iron) and deposited as manganese oxides elsewhere in the weathering profile.
The assays also show that the majority of manganese resides towards the south at the back of the valley
(Figure 6). This dispersion is due to the higher-grade nodules being heavier than the lower grade nodules
which contain lighter minerals such as iron oxides and silicates from the source chert. This can be seen by
the grade distribution in Figure 6, where water movement is towards the top of the image (north).
This dispersion of grade indicates that water flow down the valley floor during the wet season is sorting and
concentrating high-grade nodules and washing away the lighter minerals further down the valley. These
are good directional indicators in exploration that point towards the zones of economic interest in the hills
above the valley floor.
Figure 6: Location of Sica tertiary manganese assays showing a sharp increase in grade to the south, heading towards the
supergene sub-crop area.
The average phosphorus grade for all the samples is 0.17% when not including chert contaminated samples
CBR114607 – CBR104610, which represent the lighter material washed towards the northern foot of the
valley. CBR114609 appears to have been lost in transit through Australian customs and did not arrive at
the lab.
Estrella submitted all samples for additional testing to ascertain their boron and arsenic levels. All samples
are very low in boron and arsenic which suggests that Timor-Leste manganese should also be a marketable
product to the steel industry. Steel quality can be improved with the addition of high-grade manganese ores
that are also low in boron and arsenic. This allows for more control when creating specific steels with
properties for hardness, weldability and wear resistance.
Next Steps
The company has just completed environmental surveys on a series of planned drill positions at Ira Miri,
Sica and Lalena. These drill positions will test the recent IP survey results along with geological targets
generated by the previous 9 months of mapping.
The applications to the relevant Government bodies to allow the start of the drill campaign are currently
being submitted. Mapping of the prospective trends identified by the company’s predictive exploration
model will continue through the wet season.
The track-mounted carrier for the air compressor and a complete RC sample system (Figure 7) were
imported from Vietnam by a Darwin-based drill contractor. These items have just landed in Timor-Leste
and are being cleared through customs.
The multipurpose drill rig to be used on the projects will leave Darwin in March with additional RC rods and
hammers to complement the existing stocks already in Timor-Leste.
The end of the wet season in March-April should coincide with the completion of full RC drill capability in
Timor-Leste.
Figure 7: Track-mounted carrier for the compressor and the RC sample system
The company will update shareholders as the approvals process and continued exploration unfolds.
The Board has authorised for this announcement to be released to the ASX.
FURTHER INFORMATION CONTACT
Christopher J. Daws
Managing Director
Estrella Resources Limited
+61 8 9481 0389
info@estrellaresources.com.au
Media:
David Tasker
Managing Director
Chapter One Advisors
E: dtasker@chapteroneadvisors.com.au
T: +61 433 112 936
Forward Looking Statements
This announcement contains certain forward-looking statements which have not been based solely on historical facts
but, rather, on ESR’s current expectations about future events and on a number of assumptions which are subject to
significant uncertainties and contingencies many of which are outside the control of ESR and its directors, officers and
advisers.
Competent Person Statement
The information in this announcement relating to Exploration Results is based on information compiled by Steve Warriner,
who is the Group Exploration Manager of Estrella Resources, and a member of The Australasian Institute of
Geoscientists, and based on information compiled by Beau Nicholls, who is a Director of Sahara Natural Resources and
is the Exploration Manager for Estrella Timor-Leste, and a fellow of The Australasian Institute of Geoscientists. Mr
Warriner and Mr Nicholls have sufficient experience relevant to the style of mineralisation and type of deposit under
consideration, and to the activity they are undertaking to qualify as Competent Persons as defined in the 2012 Edition of
the “Australasian Code for Reporting of Exploration Results, Mineral Resource and Ore Reserves”. Mr Warriner and Mr
Nicholls consent to the inclusion in the report of the matters based on their information in the form and context in which
it appears.
Table 3: Assay Results
Sample ID
Al2O3
%
CaO
%
Fe2O3
%
K2O
%
MgO
%
MnO
%
Na2O
%
P2O5
%
SO3
%
SiO2
%
TiO2
%
LOI %
As
ppm
B
ppm
CBR114606
2.62
21.34
24.43
0.31
1.41
12.8
0.4
13.86
0.53
7.38
0.1
13.36
23.9
40
CBR114607
2.49
22.83
26.08
0.31
0.87
11.12
0.42
15.09
0.64
7.51
0.09
9.79
40.8
40
CBR114608
2.91
20.16
23.15
0.52
0.44
16.08
0.56
14.3
0.93
8.08
0.09
9.34
37.8
40
CBR114609
L.N.R.
CBR114610
3.01
15.02
22.93
0.55
0.83
22.5
0.63
9.89
0.89
10.16
0.09
11
17.45
40
CBR114611
2.89
2.06
17.96
0.67
1.18
42.15
0.98
0.41
0.25
14.54
0.08
12.95
18.8
30
CBR114612
2.84
2.32
14.44
0.7
0.98
46.91
0.88
0.42
0.19
13.19
0.08
12.83
19.45
30
CBR114613
3.07
3.22
21.82
0.53
1.36
34.05
0.65
0.38
0.38
13.81
0.1
17.18
6.92
30
CBR114644
2.49
2.23
20.65
0.58
1.26
42.86
0.46
0.18
0.6
8.17
0.08
16.84
20.8
30
CBR114645
4.08
1.7
18.81
0.83
1.31
35.16
0.98
0.23
0.22
20.22
0.14
12.87
5.01
40
CBR114646
4
2.76
24.3
0.66
1.22
30.59
0.8
0.17
0.59
16.89
0.14
14.6
8.73
40
CBR114647
3.64
1.61
22.69
0.7
1.23
34.22
1.08
0.18
0.91
15.73
0.14
13.41
27
40
CBR114648
3.45
2.48
21.68
0.75
1.23
36.89
0.88
0.17
0.4
15.2
0.11
14.12
8.42
40
CBR114649
2.65
2.9
22.87
0.4
1.46
35.05
0.41
0.14
0.47
10.34
0.09
20.27
2.48
30
CBR114650
3.21
2.46
24.28
0.53
1.35
34.74
0.49
0.1
0.9
10.36
0.12
18.11
52.3
40
CBR114651
1.53
4.05
7.68
0.65
0.69
58.97
0.58
0.08
0.11
5.53
0.02
14.59
27.5
30
CBR114652
0.9
1.39
1.45
0.52
0.15
73.16
0.17
0.21
0.02
3.41
<0.01
12.39
75.1
10
CBR114653
4
2.45
20.39
0.64
1.37
31.03
0.86
0.19
0.67
18.58
0.14
15.53
4.85
40
CBR114654
1.23
3.66
5.54
0.25
0.39
64.03
0.28
0.1
0.1
4.92
0.04
14.24
62.5
20
CBR114655
1.52
2.87
5.9
0.35
0.42
62.83
0.34
0.26
0.08
6.44
0.03
13.08
63.3
20
CBR114656
1.16
3.36
1.6
0.25
0.26
67.4
0.21
0.07
0.04
6.65
0.01
13.47
78.8
10
CBR114657
0.92
2.54
2.07
0.38
0.22
69.86
0.19
0.1
0.02
3.78
<0.01
13.3
63.7
10
CBR114658
0.96
3.42
1.45
0.16
0.2
68.36
0.16
0.31
0.06
4.61
<0.01
13.48
73.5
20
CBR114659
2.22
0.97
11.58
0.89
0.5
57.54
0.38
0.05
0.09
7.95
0.04
12.44
2.87
30
CBR114660
1.95
1.58
11.34
0.86
0.66
57.18
0.73
0.06
0.05
7.16
0.03
12.96
5.51
30
CBR114661
2.02
1.62
10.55
0.83
0.76
56.13
0.81
0.08
0.21
8.84
0.03
12.56
9.86
30
CBR114662
2.21
1.89
9.52
0.87
0.92
54.28
0.89
0.4
0.05
10.92
0.04
12.53
6.7
30
CBR114663
2.31
0.96
11.36
0.8
0.72
55.96
0.74
0.04
0.06
9.68
0.05
12.45
1.72
30
CBR114664
2.99
3.16
11.88
0.87
1.19
47.11
0.94
0.28
0.12
13.78
0.09
13.85
3.29
40
CBR114665
2.12
1.79
9.96
0.86
1.03
55.1
0.93
0.05
0.07
9.83
0.05
13.05
10.55
30
CBR114666
2.88
2.71
9.77
0.96
1.4
44.42
1
0.55
0.12
19.54
0.09
12.57
10.4
40
CBR114667
2.9
2.16
9.42
0.98
1.42
44.9
1.1
0.2
0.08
19.04
0.09
12.92
9.94
40
CBR114668
3.03
2.01
8.96
1
1.53
43.34
1.2
0.34
0.09
21.63
0.1
12.39
4.82
40
CBR114669
2.39
2.31
16.42
0.78
0.87
47.83
0.73
0.38
0.09
10.46
0.07
13.05
6.4
40
CBR114670
1.22
3.39
3.05
0.61
0.42
66.93
0.34
0.13
0.07
4.15
0.02
14.12
61.9
20
CBR114671
1.09
2.99
1.66
0.21
0.22
68.94
0.18
0.06
0.03
4.66
0.01
13.52
71.9
20
CBR114672
1.29
1.23
2.5
0.54
0.26
69.13
0.22
0.1
0.02
5.68
0.03
12.13
84.6
10
CBR114673
1.91
1.92
8.59
0.62
0.58
59.7
0.48
0.09
0.23
6.52
0.05
12.94
58.3
20
CBR114674
0.88
3.15
2.86
0.51
0.34
67.18
0.34
0.12
0.05
4.02
<0.01
13.88
68.2
10
CBR114675
1.19
2.66
3.14
0.22
0.66
68.12
0.23
0.09
0.06
4.5
0.05
13.57
69.6
10
CBR114676
1.8
2.28
5.76
1.74
0.53
61.01
0.48
0.23
0.05
8.16
0.04
12.52
45.9
20
CBR114677
1.26
2.96
2.44
0.3
0.36
66.89
0.32
0.08
0.04
5.34
0.01
13.33
71
20
CBR114678
0.96
3.58
2.11
0.44
0.28
68.62
0.24
0.1
0.05
3.8
<0.01
13.99
61.3
10
CBR114679
0.98
2.42
1.28
0.21
0.23
70.19
0.21
0.08
0.02
3.36
0.01
13.3
80.9
20
CBR114680
1.19
1.82
0.96
0.18
0.16
73.67
0.13
0.07
0.01
3.25
0.02
12.86
76.7
10
CBR114681
1.04
3.34
2.02
0.21
0.29
68.45
0.25
0.12
0.04
4.94
0.01
13.71
68.3
10
CBR114683
1.49
3.94
6.08
0.94
0.88
60.02
0.86
0.06
0.05
6.75
0.02
14.49
19.3
20
CBR114684
1.03
2.49
2.74
0.18
0.2
70.45
0.17
0.09
0.03
3.45
0.02
13.33
69.7
10
CBR114685
1.89
2.12
2.09
0.59
0.9
51.59
0.28
0.13
0.02
20.83
0.05
14.51
14
10
CBR114686
1.05
1.83
0.81
0.28
0.45
66.19
0.49
0.04
0.25
8.85
0.01
13.3
3.2
10
CBR114687
3.31
12.68
2.32
0.35
1.11
25.36
0.41
4.62
0.22
37.56
0.08
9.7
8.91
40
CBR114689
0.61
0.82
0.56
0.08
0.09
75.39
0.11
0.11
0.46
2.24
<0.01
12.34
315
10
CBR114690
0.67
0.99
0.67
0.07
0.02
75.66
0.08
0.3
0.06
1.61
<0.01
12.75
48.5
10
CBR114691
1.67
0.93
11.03
1.31
0.53
59.35
0.49
0.07
0.04
6.76
0.03
12.78
0.5
20
CBR114692
1.43
1.15
4.6
1.08
0.7
63.61
0.43
0.07
0.04
8.08
0.01
12.58
2.62
20
APPENDIX 1 JORC TABLE 1 – TIMOR-LESTE EXPLORATION
Section 1 - Sampling Techniques and Data
Criteria
Sampling
techniques
Drilling
techniques
Drill sample
recovery
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 (e.g. submarine
nodules) may warrant disclosure of detailed
information.
• 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, face-sampling bit or other
type, whether core is oriented and if so, by
what method, etc).
Commentary
•
Determination of mineralisation has been
based on geological mapping, visual
mineral estimates and confirmation of
metallic concentration using a Bruker S1
Titan Portable XRF instrument.
•
Initial rock-chip samples were taken and
pXRF determinations on uncrushed
samples made in the field.
•
Samples are then brought back to Dili and
pulverized to 100% passing 1mm before
the powder is again subjected to PXRF
•
A sub-sample of 300g is then dispatched
through customs and quarantine in
Australia to ALS in Malaga for multielement analysis.
•
Exported samples are analysed using a 4acid digest, ME-XRF26s, ME-MS61L and
B-ICP69 at ALS in Malaga
•
No drilling has been undertaken to date.
•
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.
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.
•
•
No drilling has been undertaken to date.
The installation of pulverising sample prep
facilities in Timor-Leste ensures sample
representivity when presented to the PXRF
and when obtaining the 300g split to send
to Australia.
•
Rock-chip samples were geologically
logged
for
mineral
content
and
photographed prior to sending for assay or
screening by pXRF.
•
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
•
Sample sizes are appropriate to the grain
size of the mineralisation which in
manganese oxides is very fine.
The exploration program is in its very early
stages and initial sample sizes are kept
small due to freight and customs /
quarantine restrictions. They are not
considered representative of the bulk of
mineralisation.
•
•
Logging
•
•
•
Subsampling
techniques
and sample
preparation
•
•
•
•
Criteria
Quality of
assay data
and
laboratory
tests
JORC Code explanation
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.
• 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 bias) and
precision have been established.
Commentary
•
•
•
•
•
•
Verification
of sampling
and
assaying
Location of
data points
•
•
•
•
•
•
•
Data spacing
and
distribution
•
•
•
Orientation
of data in
relation to
geological
structure
•
•
The verification of significant intersections
by either independent or alternative
company personnel.
The use of twinned holes.
Documentation of primary data, data entry
procedures, data verification, data storage
(physical and electronic) protocols.
Discuss any adjustment to assay data.
Accuracy and quality of surveys used to
locate drill holes (collar and down-hole
surveys), trenches, mine workings and other
locations used in Mineral Resource
estimation.
Specification of the grid system used.
Quality and adequacy of topographic
control.
Data spacing for reporting of Exploration
Results.
Whether the data spacing and distribution is
sufficient to establish the degree of
geological and grade continuity appropriate
for the Mineral Resource and Ore Reserve
estimation procedure(s) and classifications
applied.
Whether sample compositing has been
applied.
Whether the orientation of sampling
achieves unbiased sampling of possible
structures and the extent to which this is
known, considering the deposit type.
If the relationship between the drilling
orientation and the orientation of key
mineralised structures is considered to have
•
Three sample types are quoted:
1 – Uncrushed Field PXRF (a fresh mineral
face is chipped from samples prior to the
XRF determination in the field)
2 – Crushed PXRF (samples from above
are taken back to Dili, 1-3kg of material,
and crushed/pulverised to 100% passing
1mm in the company’s dedicated sample
preparation facility, and 15g of powder is
then taken for PXRF analysis. Crushed
PXRF
determinations
have
been
subjected to repeat samples, standards
and confirmation of accuracy by laboratory
analysis.
3 – Assay, where 150g of material is
exported to ALS in Malaga via quarantine
in Darwin. Standards and blanks have not
been included in samples sent to Australia.
The company relies on the internal
standards and blanks used by ALS.
Samples are being analysed at ALS in
Malaga using a 4-acid digest, ME-ICP for
61 elements and all samples are also
being tested for Pt, Pd and Au by fire assay
and ICP-MS finish on a 50g sub-sample.
Currently, uncrushed field samples are
being analysed by PXRF on location,. The
Cautionary statement is included when
assessing pXRF.
No prior modern exploration has been
conducted in the area.
•
No adjustments to assay data were
undertaken save where the ME-XRF26s
method reports MnO%.
•
Mn% is derived by dividing MnO by 1.2912
•
Timor personnel use GRID software on
mobile phones to record GPS locations,
sampling data and photographs. Mobile
phone accuracy (shown during coordinate
capture) is set at a maximum tolerance of
5m.
Topographic control is accomplished
using 30m spaced satellite point data.
No systematic sampling has been
conducted at this early stage.
•
•
•
No orientation-based sampling bias has
been identified.
Criteria
Sample
security
JORC Code explanation
introduced a sampling bias, this should be
assessed and reported if material.
• The measures taken to ensure sample
security.
Commentary
•
•
Audits or
reviews
•
The results of any audits or reviews of
sampling techniques and data.
•
•
•
Exported samples are in the possession of
ESR personnel from field collection to
customs
submission
in
Darwin.
Possession
then
passes
to
the
Department of Agriculture, Forestry and
fisheries where Northline Couriers pick up
the samples and take them by road to ALS
in Malaga.
Non-exported samples remain with ESR
personnel past Darwin Airport Customs.
No independent audit or review has been
undertaken.
Internal QAQC involves frequent standard
checks on the PXRF instrument to
determine any drift of accuracy.
Additional checks involve analysis of any
assayed samples in comparison to the
crushed and uncrushed in-country PXRF
determinations so as to provide
confidence in in-country analysis.
Section 2 - Reporting of Exploration Results
Criteria
Mineral
tenement and
land tenure
status
JORC Code explanation
• Type, reference name/number, location and
ownership including agreements or material
issues with third parties such as joint
ventures, partnerships, overriding royalties,
native title interests, historical sites,
wilderness
or
national
park
and
environmental settings.
• The security of the tenure held at the time
o
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