e50e384a-aef5-4a57-99a6-765351a0ed9f.pdf
ASX RELEASE
30 October 2015
LARGE INCREASE IN MINERAL RESOURCES FOR NOLANS PROJECT
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Total contained rare earths in higher confidence Measured and Indicated Resources at Nolans Bore now approaching one million tonnes (up 38%)
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Substantial increase in Mineral Resources brought about by key EIS studies nearing completion
Australian Rare Earths company, Arafura Resources Limited (ASX: ARU) ('Arafura' or the 'Company') is pleased to announce a significant increase in Mineral Resources for the Nolans Rare Earths Project in Australia's Northern Territory.
Total Mineral Resources at Nolans Bore are now estimated to be 56 million tonnes @ 2.6% total rare earth oxides ('TREO'). These have been classified into Measured, Indicated and Inferred Mineral Resources in Table 1 using a 1% TREO cut-off grade ('COG'). The contained (in-situ) resources of rare earths are also shown in the table, and a graphical comparison with the previous estimate reported in 2014 (ASX: ARU 09/12/14) in shown in Figure 1.
Table 1: Statement of Nolans Bore Mineral Resources at 30 October 2015 using a 1% TREO COG
RESOURCES
|
TONNES
million
|
RARE EARTHS TREO %
|
TONNES TREO
|
PHOSPHATE P2O5 %
|
URANIUM
U3O8 lb/t
|
Measured
|
4.9
|
3.2
|
158,000
|
13
|
0.54
|
Indicated
|
30
|
2.7
|
816,000
|
12
|
0.44
|
Inferred
|
21
|
2.3
|
489,000
|
10
|
0.36
|
TOTAL
|
56
|
2.6
|
1,462,000
|
12
|
0.42
|
Numbers may not compute exactly due to rounding. 1 lb/t U3O8 = 0.0454%U3O8.
AN EMERGING RARE EARTHS PRODUCER FOR USERS WORLDWIDE
Figure 1: Comparison between current (2015) and previous (2014) estimates (1% TREO COG)
ARAFURA RESOURCES LIMITED
[email protected] www.arultd.com ABN 22 080 933 455
PERTH: Level 3/263 Adelaide Tce, Perth WA 6000 | PO Box 5773, St Georges Terrace, Perth WA 6831 T: +618 6210 7666 F: +618 9221 7966
DARWIN: 18 Menmuir St, Winnellie NT 0820 | PO Box 37220, Winnellie NT 0821 T: +618 8947 5588 F: +618 8947 5599
Both the current and previous resource estimates have been reported and classified in accordance with the guidelines of the 2012 edition of the JORC Code. The comparison between these estimates highlights increases in:
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Contained TREO in Measured Resources of 14,000 tonnes, or 10%;
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Contained TREO in Indicated Resources of 253,000 tonnes, or 45%; and
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Total contained TREO at Nolans Bore of 245,000 tonnes, or 20%.
Higher confidence Measured and Indicated ('M&I') Resources now account for two-thirds, or 974,000 tonnes, of the Nolans Project's total contained TREO. Their spatial distribution (using a 1% TREO COG) is shown in Figure 2 below, and this highlights the coherent nature of the substantially larger inventory of Indicated Mineral Resources across the North, Central and Southeast zones of the deposit.
Figure 2: Distribution of Measured, Indicated and Inferred Resources at Nolans Bore
The impetus for this resource update was the necessity to characterise the Project's life-of- mine waste rocks, including their radioactivity, which is a key component of the Nolans Environmental Impact Statement ('EIS') studies that are now nearing completion. This comprehensive review by Arafura's geologists led to the development of a new and improved geological model for mineralisation at Nolans Bore which has been adopted for this estimate.
While no additional drilling has occurred on the Project since the 2014 estimate, there are a number of important factors that have resulted in an overall increase in Mineral Resources and enabled the classification of more resources into the higher confidence M&I categories. They are:
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Revision and remodelling of the geometry of the deposit and related oxidation states;
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Where consistent with geological continuity, extrapolation of geological units from drill intersections by a distance equal to at least half the principal drill spacing so as
to ensure that waste rocks and mineralisation were equally represented in the new geological model. Some geological bodies were interpolated by more than this distance at depth but only where they were supported across multiple drill sections;
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Inclusion of a number of mineralised objects that were overlooked in the previous estimate (now 138, previously 102); and
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Adoption of 3D search parameters with steep or inclined down-dip orientations for the mineralisation, which differ from those used in the previous estimate.
The new resource classification is based on a 1% TREO cut-off grade and this classification might not be applicable to other cut-off grades. Total Mineral Resources reported at a range of cut-off grades is listed in Table 3 and shown graphically in Figure 3. This indicates that the Mineral Resources are insensitive to cut-off grade in the 0-1.5% TREO range.
Table 3: 2015 Mineral Resources reported at a range of COGs
CUT-OFF GRADE %
|
TONNES
million
|
RARE EARTHS TREO %
|
PHOSPHATE P2O5 %
|
URANIUM
U3O8 lb/t
|
0.5
|
56
|
2.6
|
11
|
0.41
|
1.0
|
56
|
2.6
|
12
|
0.42
|
1.5
|
50
|
2.8
|
12
|
0.44
|
Figure 3: 2015 estimate Grade-Tonnage Curve for Rare Earths
- ENDS -
For further information contact: Media enquiries:
Gavin Lockyer Rebecca Lawson
Managing Director Media+Capital Partners
T: +61 8 6210 7666 M: +61 433 216 269
Summary of Material Information
Mineralisation at Nolans Bore is a three-dimensional, stockwork vein-style deposit and is now broadly subdivided into the North, Central, Southeast and Southwest zones as shown in Figure 2. The geological model portrays the geometry of an enveloping surface that encompasses all Nolans Bore mineralisation and its associated alteration using a nominal 0.5% REE cut-off grade whilst minimising the amount of internal waste. Isolated narrow intervals of mineralisation have been excluded from the geological model where drill intersections are less than 2 metres and there is no support in adjacent holes.
The geological model builds on all geological, geophysical, and geochemical data systematically acquired by Arafura since 2000 and has greatly benefited from targeted drilling in different directions. The current resource model is based on sectional interpretations, wireframing and three dimensional solid geological models of the mineralised zones. Not all mineralisation has been captured in the resource model however more material is included in the current model.
There is only a limited number of basement outcrops with most of the area covered by a thin veneer of soil, alluvium, colluvium and calcrete. Drilling indicates the widespread presence of mineralised veins up to tens of metres in thickness and hundreds of metres in length, extending below 215 metres depth across parts of the deposit. The full extent of the deposit is yet to be outlined but deeper drilling has demonstrated mineralisation and alteration at about 430 metres depth in the North Zone.
The fluorapatite mineralisation ranges from discrete narrow fine-grained veins to wide intervals of massive coarse-grained breccias. The fluorapatite-rich rocks contain up to about 95% fluorapatite and typically contain abundant mineral inclusions of REE-bearing minerals, such as monazite group minerals, allanite, thorite and numerous other REE phosphates, silicates and carbonates. The fluorapatite itself contains variable amounts of REE but a higher proportion of REE is hosted in the mineral inclusions.
A total of 87,081 metres of reverse circulation ('RC') and Diamond core drilling plus 1,112 metres of costeans has been included in the database used for the current estimate of Mineral Resources. The proportion of Diamond drill core is sufficiently high (31%) to provide a good geological understanding of the deposit. The deposit has been systematically drilled using a nominal 40 metre x 40 metre spaced collars inclined at -60° along drill sections oriented at 145 degrees true. Closer spaced 20 metre x 20 metre infill drilling has occurred in the North Zone. A number of holes have also been drilled in other directions for geotechnical purposes and to resolve geological complexities in the model. Data from 1,656 metres of bulk sample metallurgical drilling was used to support geological interpretation, but in the absence of representative assays was excluded from the grade estimate.
A set of sectional geological interpretations that define the enveloping surface for all identified REE mineralisation were created using a 0.5% REE cut-off grade. Geological objects were edited and modified using Surpac v6.6, referring back to the original sectional interpretation as appropriate. New surfaces were also generated for the topography, base of soil, standing water level, base of oxidation and top of fresh. All surfaces and geological objects were then rotated to a new local grid and validated.