high grade phosphate mineralisation extended

Uramet Minerals Limited
Level 1, 130 Hay Street
Subiaco WA 6008
PO Box 8280
Subiaco East WA 6008
AUSTRALIA
Tel: +61 (0)8 6380 2799
Fax: +61 (0)8 6380 1644
Email: [email protected]
Web Site: www.uramet.com.au
Media Release 19 June 2008
High-Grade Phosphate Mineralisation Extended in Uramet’s Marqua Area
HIGHLIGHTS
♦ Field work and re-assays extend phosphate discovery zone along 25 km of strike length
♦ Outcropping phosphate rock samples of up to 32.7% P2O5 identified at Foss Hill prospect
♦ Up to 24.8% P2O5 in core from historical drill hole and up to 22.3% P2O5 in outcropping phosphate rock at Coquina Creek prospect
♦ White Hill prospect includes 24.1% P2O5 at surface
♦ Aircore drill program for phosphate in Marqua area scheduled for July 08
♦ Follow up ground exploration work at Bar Creek project area located adjacent to the substantial Lady Annie deposit owned by Legend International Holdings scheduled to commence 25 June 2008.
♦ RAB drilling at the Box Hole Pb-Zn Project to commence 22 June 2008
Fig. 1 Uramet Phosphate Prospects, Marqua Project Area
ERB218-220 and MQ13 are drill hole, and A102808-12 are surface samples reported on 8 May 2008
2
RESULTS OF FIELD TRIP TO THE MARQUA PROJECT AREA
In late May-early June 2008, a field trip was undertaken to areas prospective for phosphate in Uramet’s Marqua Project area (within the southern Georgina Basin) located approximately 450km east of Alice Springs. The Marqua area comprises the two Boat Hill tenements and the Desert Syncline tenement in the Northern Territory plus the two Toko tenements in Queensland. See Fig 1.
• On the western Boat Hill tenement, within the Cambrian Thorntonia Limestone unit,
o at Foss Hill, the nature and extent of previously known high-grade phosphorite mineralization was defined
o at Coquina Creek, Library Ridge and White Hill, additional high-grade phosphorite sites were discovered
o at Mauritania located west of Red Heart (where phosphate mineralization was previously recorded), anomalous phosphate was identified which requires further investigation.
• On the eastern Boat Hill tenement, within the Ordovician Mithaka Formation,
o at Horseshoe and Toomba, anomalous phosphate was identified requiring further investigation.
• On the Desert Syncline tenement,
o at HR11 and Syncline, anomalous phosphate was identified which requires further investigation.
• This field trip confirmed the phosphate prospectivity of the Cambrian Thorntonia Limestone unit over a 25 km strike length from the Library Ridge prospect to the Mauritania prospect.
• The field trip has also confirmed the phosphate prospectivity of the Ordovician Mithaka Formation which has not been subject to any previous exploration for phosphate. On Fig 1, the Mithaka Formation is the “prospective stratigraphy” shown in green in the eastern Boat Hill and Toko tenement areas.
• Sufficient investigations have now been conducted on the ground to allow drill targets to be defined at all the high-grade prospects.
• An aircore drill program for phosphate in the Marqua area is planned to commence in July 2008
In this announcement, assay results are reported from (a) rock outcrop and soil samples collected in the field and (b) from historical drill spoils and core stored at the NTGS core library (Alice Springs) and in the field. In Tables 1 to 6 below, high-grade phosphate (≥15% P2O5) is highlighted in red.
Details of the analytical method used are set out in the Appendix.
Foss Hill Prospect
At the Foss Hill prospect, outcropping phosphorite was located over a strike length of 550 m and maximum true width of 60 m tapering towards the NW end. The SE extension is covered by sand. The phosphorus is hosted in phosphatised shelly beds (coquinite) and phosphatic mudstone and wackestone of the Cambrian age Thorntonia Limestone unit.
The phosphorite beds at Foss Hill have been tilted steeply to the north (average 75 degrees) so that the outcrop width is close to true thickness. See Fig 2. Rock outcrop and soil samples were taken at 2 metre intervals along a traverse across the phosphatic beds. See Fig 3. The assay results from this traverse are given in Table 3. This provides a guide to the width and tenor of the phosphate mineralization that can be expected in the Marqua project area. The vertical dip at Foss Hill is very localized; the phosphorite beds are generally shallow-dipping elsewhere.
Four phosphorite intervals along this traverse (29m, 8m, 8m and 15m thick) are separated by chert bands. The average rock chip analyses of the four intervals are summarized in Table 1 below:
Table 1. Foss Hill traverse - average assay results – Portable XRF Analysis
Interval
Width (m)
Sample No.
Av. % P2O5
Max. % P2O5
Interval 1
29
QTRS01-15
19.9
32.7
Interval 2
8
QTRS23-26
10.4
13.6
Interval 3
8
QTRS29-32
10.7
19.0
Interval 4
15
QTRS36-43
17.7
25.4
Fig 2. Profile of the traverse across the Thorntonia Limestone unit at Foss Hill
Fig 3. Looking SW along the traverse at Foss Hill. Samples were taken every two metres.
3
4
A number of other samples from Foss Hill (and other prospects) were analysed by portable XRF. See Table 2
.
Coquina Creek Prospect
A new site of phosphorite outcrop was located 1.2 km along strike east of Foss Hill. Phosphate rocks up to 22.3% P2O5 at surface (Table 2) were located over a strike length of 400m. Phosphate rocks up to 24.8% P2O5 were located in nearby historical base metal exploration holes M13P, BHD5 and BHD6 (Table 4).
Library Ridge Prospect
Phosphate rock outcrop was located 5.5 km along strike east of Foss Hill. Phosphatic rocks with up to 12.1% P2O5 occur at surface (Table 2), although much of this area is covered by thin sand and rock scree which obscures outcrop. Intervals of phosphatic rocks have been located at depth in historical base metal exploration holes MQ5 and MQ6 (Table 6).
The intervals include:
• 8 m at 6.5% P2O5 with a peak assay of 14.7% P2O5 over 1 m from 8 m depth in hole MQ5
• 4 m at 9.1% P2O5 with a peak assay of 16.5% P2O5 over 1 m from 10 m depth in hole MQ6
White Hill Prospect
New phosphorite outcrops with up to 24.1% P2O5 have been located in shelly beds over a strike length of 400 m, although encroaching sand cover has obscured much of the outcrop in this area. The sites were located near historical base metal exploration hole MQ13 (see Fig 1) where a 13.7% P2O5 sample was previously identified in drill spoils.
Drill chips from adjacent hole MQ12 were re-assayed yielding a 6 m interval at 7.7% P2O5 with a peak assay of 14.8% P2O5 over 1 m from 12 m depth (Table 5).
A further 1.3 km to the west shelly beds were also encountered, however, these beds are strongly silicified at surface which has downgraded their phosphate content with a maximum of 5.7% P2O5 recorded (Table 2). The silicification is only a surface feature and the phosphate grade is expected to increase at depth.
There is potential at White Hill for phosphorite to occur over 2.5 km of strike length. The beds here dip only shallowly to the north and are mostly obscured by thin sand cover. The phosphorite coincides with conductivity anomalies identified from last year’s VTEM airborne survey. The conductivity features may arise from interbedded black shales, which will assist in tracing the phosphate beds under cover.
Mauritania Prospect
Re-assay of drill spoils from historical holes MQ16 and MQ17 confirms that phosphatic rocks are located along strike 13 km west of White Hill. A maximum assay of 7.2% P2O5 was recorded at 6 m depth in hole MQ16 (Table 5). In this area no outcrop of phosphatic rocks has been located because of extensive sand cover.
5
Toomba and Horseshoe Prospects
Outcropping phosphatic sandstone of the Ordovician Mithaka Formation was located in two areas west of the NT - Queensland border within the Toko Syncline. A maximum assay result of 10.5% P2O5 was recorded from white phosphatic sandstone at the Horseshoe Prospect and 2.7% P2O5 was recorded from a similar rock at the Toomba Prospect (Table 2). Potash-rich rocks (up to 8.1% K2O) have also been located at the Toomba Prospect (Table 2).
This result confirms the phosphate prospectivity of the Ordovician Mithaka Formation which is younger than the Cambrian Georgina Basin formations that have traditionally been explored for phosphate.
HR11 Prospect and Syncline Prospect
Phosphatic sandstone/siltstone with a maximum assay result of 5.4% P2O5 and potash-rich siltstone with 7.6% K2O (Table 2) was located in the basal Cambrian Red Heart Dolostone (a unit that underlies the Thorntonia Limestone) at the HR11 Prospect.
Table 2. Marqua Area - Surface Rock Chip Samples – Portable XRF Analysis
Sample Location
Sample No
Prospect
Rock Description
P2O5%
K2O%
MGA_E
MGA_N
QMNS505
Foss Hill
shelly phosphorite
16.7
0.0
768653
7466319
QMNS506
shelly phosphorite
18.8
0.1
768672
7466360
QMNS512
silicified phosphate rock
8.2
0.0
768708
7466350
QMNS514
shelly phosphate rock
14.5
0.0
768901
7466183
QMRS585
shelly phosphorite
17.0
0.0
768431
7466457
QMNS537
Library Ridge
white phosphatic mudstone
12.1
0.1
774010
7466271
QMNS538
white phosphatic mudstone
11.0
0.1
774234
7466275
QMRS520
Coquina Creek
shelly phosphorite
22.3
0.0
769927
7466113
QMRS527
ferruginous calcareous coquinite
12.3
0.0
769744
7466197
QMRS549
White Hill
shelly phosphorite
24.1
0.0
763184
7467871
QMRS550
shelly phosphorite
21.2
0.0
762830
7467843
QMRS554
white phosphatic claystone
5.7
0.6
761534
7467518
QMRS606
Horseshoe
white phosphatic sandstone
9.4
0.5
805007
7460866
QMRS611
white phosphatic sandstone
10.5
0.6
804995
7460854
QMRS617
Toomba
?alunite-rich rock
<2.5
8.1
799466
7456509
QMRS619
phosphatic sandstone
2.7
0.5
799891
7456373
QMRS627
HR11
?alunite-rich siltstone
<3.2
7.6
759004
7440009
QMRS635
yellow laminated sandstone
4.8
0.6
759157
7440035
QMRS636
phosphatic sandstone-siltstone
5.2
1.0
759164
7440012
QMRS638
Syncline
weathered Cretaceous sandstone
4.4
0.7
767148
7441383
6
Table 3. Foss Hill - soil and rock chip samples at 2 m intervals – Portable XRF Analysis
Sample Location
Sample No
Rock Description
Sample Type
P2O5%
MGA_E
MGA_N
QTRS001
shelly phosphorite
soil rock chips
31.5
768718.0
7466354.0
QTRS002
shelly phosphorite
soil rock chips
15.1
768716.4
7466352.8
QTRS003
shelly phosphorite
soil rock chips
19.9
768714.8
7466351.7
QTRS004
shelly phosphorite
soil rock chips
21.4
768713.3
7466350.5
QTRS004
silicified phosphorite
rock outcrop
<3.3
768713.3
7466350.5
QTRS005
shelly phosphorite
soil rock chips
26.4
768711.7
7466349.3
QTRS006
shelly phosphorite
soil rock chips
21.4
768710.2
7466348.2
QTRS006
shelly phosphorite
rock outcrop
14.0
768710.2
7466348.2
QTRS007
shelly phosphorite
rock outcrop av.
20.3
768708.6
7466347.1
QTRS007
shelly phosphorite
soil rock chips
13.0
768708.6
7466347.1
QTRS008
shelly phosphorite
soil rock chips
16.1
768707.0
7466345.9
QTRS009
shelly phosphorite
rock outcrop av.
32.7
768705.5
7466344.8
QTRS010
shelly phosphorite
soil rock chips
28.5
768703.9
7466343.8
QTRS011
shelly phosphorite
soil rock chips
21.4
768702.4
7466342.7
QTRS011
shelly phosphorite
rock outcrop av.
17.3
768702.4
7466342.7
QTRS012
shelly phosphorite
soil rock chips
14.3
768700.8
7466341.5
QTRS013
shelly phosphorite
soil rock chips
17.0
768699.2
7466340.4
QTRS014
shelly phosphorite
soil rock chips
9.8
768697.7
7466339.3
QTRS015
shelly phosphorite
soil rock chips
20.5
768696.1
7466338.2
QTRS016
chert
soil rock chips
<1.7
768694.6
7466337.1
QTRS017
chert
soil rock chips
<1.8
768693.0
7466336.0
QTRS018
chert
soil rock chips
<1.9
768691.4
7466334.9
QTRS019
chert
soil rock chips
<1.8
768689.9
7466333.7
QTRS020
chert
soil rock chips
<1.8
768688.3
7466332.6
QTRS021
chert
soil rock chips
<1.5
768686.8
7466331.5
QTRS022
chert
soil rock chips
<1.5
768685.2
7466330.5
QTRS023
wackestone
soil rock chips
11.7
768683.6
7466329.3
QTRS024
wackestone
soil rock chips
7.5
768682.1
7466328.2
QTRS025
wackestone
soil rock chips
13.6
768680.5
7466327.1
QTRS026
wackestone
soil rock chips
11.3
768679.0
7466325.9
QTRS026
wackestone
rock outcrop
5.9
768679.0
7466325.9
QTRS027
chert
soil rock chips
<1.4
768677.4
7466324.8
QTRS028
limonitic chert
soil rock chips
<2.6
768675.8
7466323.8
QTRS029
wackestone
soil rock chips
5.2
768674.3
7466322.7
QTRS030
wackestone phosphorite
soil rock chips
15.0
768672.7
7466321.5
QTRS031
chert
soil rock chips
<3.6
768671.2
7466320.4
QTRS032
wackestone phosphorite
soil rock chips
19.0
768669.6
7466319.3
QTRS033
white claystone
soil rock chips
<1.8
768668.0
7466318.1
QTRS034
white siltstone
soil rock chips
<2.5
768666.5
7466317.0
QTRS035
wackestone
soil rock chips
7.8
768664.9
7466316.0
QTRS036
wackestone phosphorite
rock outcrop
20.3
768663.4
7466314.9
QTRS036
wackestone
soil rock chips
14.0
768663.4
7466314.9
QTRS037
wackestone phosphorite
soil rock chips
22.1
768661.8
7466313.7
QTRS037
wackestone phosphorite
rock outcrop av.
19.4
768661.8
7466313.7
QTRS038
wackestone
soil rock chips
14.8
768660.2
7466312.6
QTRS039
wackestone
soil rock chips
13.2
768658.7
7466311.5
QTRS040
wackestone
soil rock chips
12.8
768657.1
7466310.4
QTRS041
wackestone phosphorite
soil rock chips
17.5
768655.6
7466309.3
QTRS042
wackestone phosphorite
soil rock chips
19.7
768654.0
7466308.2
QTRS043
wackestone phosphorite
soil rock chips
25.4
768652.4
7466307.1
QTRS044
white siltstone
soil rock chips
<2.6
768650.9
7466305.9
QTRS051
white claystone
rock outcrop
<1.3
768640.0
7466298.1
7
Table 4. Coquina Creek - Historical Drill Holes – Portable XRF Analysis
Hole No
Depth_from
Depth_to
Prospect
Rock Description
P2O5 %
M13P
12.0
15.0
Coquina Creek
claystone
<2.4
15.0
18.0
claystone
14.9
18.0
21.0
claystone
5.1
21.0
24.0
claystone
<2.4
24.0
27.0
chert
<2.1
27.0
31.0
chert
3.0
31.0
34.0
chert
<1.7
BHD6
31.6
31.6
Coquina Creek
phosphatic mudstone
10.8
31.3
31.3
phosphatic mudstone
16.4
BHD5
462.6
462.6
Coquina Creek
shelly rock
<6.4
462.7
462.7
shelly phosphorite
24.8
463.6
463.6
mudstone
<12.0
Table 5. White Hill and Mauritania - Historical Drill Holes – Portable XRF Analysis
Hole No
Depth from
Depth to
Prospect
Rock Description
P2O5 %
MQ-12
11.0
12.0
White Hill
siltstone
<6.4
12.0
13.0
phosphatic siltstone
14.8
13.0
14.0
chert & phosphatic siltstone
7.6
14.0
15.0
phosphatic siltstone
4.3
15.0
16.0
phosphatic siltstone
4.7
16.0
17.0
phosphatic siltstone
6.2
17.0
18.0
chert & phosphatic siltstone
8.6
18.0
19.0
carbonaceous shale
<2.7
19.0
20.0
carbonaceous shale
<2.4
20.0
21.0
carbonaceous shale
4.3
21.0
22.0
carbonaceous shale
5.3
MQ-16
1.0
2.0
Mauritania
soil
<3.0
3.0
4.0
siltstone
4.9
4.0
5.0
siltstone
<3.5
5.0
6.0
chert
3.8
6.0
7.0
chert
7.2
7.0
8.0
siltstone
<2.7
MQ-17
9.0
10.0
Mauritania
siltstone & chert
<2.1
13.0
14.0
siltstone
4.6
14.0
15.0
siltstone
<2.7
8
Table 6. Library Ridge - Historical Drill Holes – Portable XRF Analysis
Hole No
Depth_from
Depth_to
Prospect
Rock Description
P2O5 %
MQ-05
0.0
1.0
Library Ridge
gypsiferous siltstone
4.5
1.0
2.0
gypsiferous siltstone
<2.5
2.0
3.0
gypsiferous siltstone
6.0
3.0
4.0
gypsiferous siltstone
14.9
4.0
5.0
gypsiferous siltstone
<3.3
5.0
6.0
gypsiferous shale & chert
2.8
6.0
7.0
gypsiferous shale & chert
2.6
7.0
8.0
siltstone
<2.5
8.0
9.0
siltstone & chert
3.8
9.0
10.0
siltstone & chert
2.6
10.0
11.0
siltstone & chert
4.3
11.0
12.0
siltstone & chert
9.7
12.0
13.0
chert & clay
14.7
13.0
14.0
chert & clay
6.1
14.0
15.0
chert & clay
7.9
15.0
16.0
chert & clay
2.7
16.0
17.0
chert & clay
<2.2
MQ-06
9.0
10.0
Library Ridge
shale
<2.7
10.0
11.0
shale
10.2
11.0
12.0
grainstone phosphorite
16.5
12.0
13.0
shale & chert
5.5
13.0
14.0
shale & chert
4.3
14.0
15.0
shale & chert
<3.1
15.0
16.0
shale & chert
3.4
16.0
17.0
shale & chert
3.0
17.0
18.0
shale & chert
3.3
18.0
19.0
shale & chert
<2.2
19.0
20.0
chert
<2.3
20.0
21.0
chert
<2.3
21.0
22.0
chert
<2.2
22.0
23.0
chert
<2.2
23.0
24.0
chert
<2.0
24.0
25.0
chert
<2.3
25.0
26.0
chert
2.9
26.0
27.0
chert
<1.9
FORWARD PROGRAM
A geological team will commence mapping and sampling at Bar Creek on 25 June 2008. The Bar Creek project area is located adjacent to the substantial Lady Annie deposit owned by Legend International Holdings. See Fig 4. The aim of the field work is to visit areas prospective for phosphorite, sample outcrops, obtain P2O5 % analyses using the portable XRF analyzer, undertake geological mapping to determine whether the phosphorite horizons extend under cover towards the SE, and define drill targets.
RAB drilling at the Box Hole lead zinc project will commence on 22 June 2008. Mobilisation of the drill rig was unfortunately delayed by unseasonal heavy rains.
Fig 4. Bar Creek Project Area
(formerly referred to as Thorntonia)
For and on behalf of the Board
W V Hewitt
Managing Director
19 June 2008
This report is based on geological information compiled by and reported upon by Dr Wayne Taylor, Chief Geologist, Uramet Minerals Ltd, a Member of the Australian Institute of Geoscientists with more than 5 years experience in the fields of activity reported. Dr Taylor has read and gives his consent to the release of this report in this form.
ENDS
Released by:
On behalf of:
Nicholas Read
The Board, Uramet Minerals Limited
Read Corporate
For further information, contact:
Telephone: (08) 9388 1474
Bill Hewitt, Managing Director
Sam Randazzo, Chairman
Telephone: (08) 6380 2799
Website: www.uramet.com.au
9
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APPENDIX
Analytical Results
All analytical data reported in this announcement were obtained with a portable Niton XRF analyser which was used during the field trip and during subsequent analytical sessions in Perth. The instrument was used to obtain assays of phosphorus and other elements in rock outcrops, soil, historical drill core and historical drill spoils, as reported above. Selected samples will be submitted for check laboratory assays.
It should be noted that any single reading by a portable Niton XRF analyzer gives a spot analysis covering an area of a few square centimetres to a maximum depth of one centimetre below the surface of the specimen being tested.
To ensure accurate phosphorus analysis, the analytical time was set to 100 seconds and a standard phosphorite sample was analysed at regular intervals during the analytical session. The laboratory assay for the phosphorite standard is 18.9%. Sixteen XRF measurements on the standard gave an average value of 18.2% with a standard deviation of 2.2%. On this basis the reported accuracy of the P2O5 measurement is considered to be better than ± 2%.
Detection limits are dependent on the sample and are determined during the analysis process by the XRF analyzer. Detection limits are generally in the range ± 2 to 5% P2O5. Because of the low energy of phosphorus X-rays, all samples including drill spoils were analysed directly on the exposed sample surface without any covering. Drill spoil rock powders were packed into plastic cups for analysis. In some cases several analyses on different parts of the same sample were averaged for a more representative value.