Ivanhoe Australia Limited
Ivanhoe Australia Limited
Exploration Ivanhoe Australia Limited
Ivanhoe Tenements
Ivanhoe Australia is also conducting an extensive regional exploration program within its Cloncurry Project tenements. With a strong history of exploration discovery and a suite of quality development projects under study on Ivanhoe Australia's Cloncurry site, the importance of regional exploration in order to extend future production scenarios remains very important.

Ivanhoe Australia's extensive tenement package is located south of Cloncurry in northwest Queensland and consists of 27 granted Exploration Permits for Minerals (EPMs) and 21 granted Mining Leases (MLs). These include 12 tenements (525 km2) under joint venture from Exco Resources. Ivanhoe Australia also has 21 EPM applications. The acquisition of the Osborne Copper Mine from Barrick Gold in September 2010 added additional exploration tenements and eight granted MLs to Ivanhoe's tenure (Figure 1).


Figure 1 - Ivanhoe Australia Exploration acreage in Cloncurry Project region.


Ivanhoe Australia's recorded exploration results during 2010 include significant drill intercepts of copper, gold, molybdenum and uranium mineralisation on the Elana M Trend (including Lanham's Shaft, Barnes Shaft and Triga prospects) as well as copper and gold intercepts at Garnet Creek 3 km. Copper and molybdenum mineralisation has also been intercepted in the Metal Ridge and Cave Hill area north of Merlin, in similar host rocks to those at Merlin.

Ivanhoe Australia's exploration team has identified targets throughout the Cloncurry tenements with prospect metals including copper, gold, molybdenum, rhenium, lead, zinc, silver, cobalt and uranium. Ivanhoe's current declared metal inventory and exploration prospects demonstrate the broad nature of the geological systems and the exploration potential.

REGIONAL EXPLORATION

The ground held by Ivanhoe Australia is one of the world's premier geological addresses, with ongoing exploration successes and recent work focussed on various styles of mineralisation which include:
  • Iron oxide-copper-gold (IOCG) prospects
  • Uranium prospects
  • Molybdenum and rhenium prospects
  • Deep polymetallic systems (copper-zinc-lead)
Regional exploration has for the last year focused on IOCG, molybdenum and uranium targets.

Regional exploration on Ivanhoe Australia's Cloncurry tenements is focussed on high priority brownfields and greenfields targets in both the recently acquired Osborne ground and the Mount Dore Trend north and south of Merlin; as well as other regional exploration targets.

Dr Murray Hitzman, the world's leading authority on iron oxide-copper-gold (IOCG) systems and an eminent geoscientist, has conducted a research program with the objective of providing a deeper understanding of the patterns of geological alteration across the Cloncurry Project tenements. Dr Hitzman, the Fogarty Professor of Economic Geology at the Colorado School of Mines in the USA, has visited the site on a number of occasions and conducted a comprehensive review of drilling results with the project's geologists. Dr Hitzman noted that the SWAN-Mount Elliott deposits represent the largest announced IOCG system discovered in Australia since Olympic Dam.

OSBORNE EXPLORATION PROJECTS

Copper and gold ore sources within the Osborne leases remain significant and will be reviewed in the coming months as part of Ivanhoe Australia's development plans. The most significant of these is the Kulthor project, for which a full feasibility study has been completed and access development is nearly complete. Work will proceed to seek to expand these resources with a vigorous Ivanhoe Australia driven exploration program commencing as soon as possible.

Kulthor

Kulthor is a copper-gold deposit 2.5 km west of the Osborne mine. Decline access to within 150 m of the orebody has been developed from the Osborne underground operation. Drilling of a planned resource upgrade program was suspended as the Osborne sale process commenced and this work still requires completion.

Osborne Open Pit Cutback

The Osborne Open Pit Cutback consists of the upper portions of the 2N orebody which has been mined at the deeper levels by the underground mine.

Lucky Luke

Lucky Luke is a shear hosted copper-gold IOCG deposit located 35 km northwest of the Osborne mine. Mineralisation comprises bornite/chalcopyrite lodes in the south and chalcocite lodes in the north. Potential to mine Lucky Luke South by open pit exists and scoping studies were commenced by Barrick personnel. The resource drilling for an initial open pit has been completed and potential also exists for additional underground resources from Lucky Luke North and South.

Duchess JV (including the Duchess and Ivanhoe Mines)

This prospect is located 15 km north of Trekelano and is shear hosted copper-gold mineralisation. In addition, geochemical anomalies have been identified on the Duchess JV that require follow-up work to potentially identify additional open pit resources.

Houdini

Recent exploration successes in the 2009 drilling campaign indicated the potential for further resources at Houdini. Following a sub-audio magnetic survey, a 500 m long near surface mineralised structure was identified following a series of significant high-grade copper-gold intercepts in this zone.

Follow up diamond drilling late 2010 returned economic grade and width intercepts on a single section down to around 300m from surface. Mineralisation at Houdini is structurally controlled. Chalcocite exists closer to the surface and within the main structure, with chalcopyrite at depth (100m) and in the footwall of the Houdini shear. Results returned to date are summarised below:
  • HOD0036 -- 6 metres @ 5.07% copper and 0.23 g/t gold from 144 metres;
  • HOD0037A -- 23 metres @ 1.51% copper and 0.25 g/t gold from 239 metres;
  • HOD0038A -- 12.5 metres @ 1.95% copper and 0.31 g/t gold from 353.5 metres;


Houdini Cross Section N7573250mN looking North


Osborne

Potential exists to discover high-grade copper-gold mineralisation in the down plunge extension of the existing Osborne system. The current mine plan has Osborne to be mined to the 135 RL, however, mineralisation has been drilled to Indicated and Inferred status to the -50 RL and exploration to date indicates copper-gold mineralisation extends to the -130 RL and below.

Limited drilling to date indicates mineralisation exists below current mine infrastructure and further drilling is required to test the depth potential of the Osborne deposit and identify potential high-grade zones.

Trekelano

The Trekelano deposit is a shear hosted copper-gold IOCG deposit located 95 km northwest of Osborne. Open pit mining of the Inheritance and Trekelano 2 deposits was completed in the third quarter of 2009.

Residual underground resources exist beneath the Inheritance open pit with down plunge potential on the north shoot. In addition, residual underground potential exists in the footwall of the historic Trekelano workings and the down plunge extent of the Trekelano deposit. Additional exploration will target this area for extensions to these systems.

THE MOUNT DORE BELT

Exploration along the Mount Dore Belt is focusing primarily on a largely undrilled 6 km long belt of strong surface copper and molybdenum mineralisation that extends northward from Merlin to Metal Ridge North (Figure 1). Copper, gold, molybdenum and cobalt mineralisation also extends at least 14 km south from Mount Dore towards Mount Cobalt, an historic cobalt mine, and the Victoria copper-gold mine (previously worked as open pits).

Ivanhoe Australia has conducted detailed rock-chip sampling, mapping, termite mound XRF surveys, ground magnetic and airborne radiometric and magnetic surveys and seismic transects along this underexplored belt.


Figure 1: The Mount Dore Belt extends for 20 km from Victoria to Metal Ridge North


The main prospects along this belt (Victoria, Mount Cobalt, Ballarae, Marilyn, Flora, Busker, Cave Hill, Metal Ridge and Metal Ridge North) all share similar geology and surface mineralisation to that at the Mount Dore and Merlin projects, with copper and molybdenum mineralisation hosted in brecciated black shales and siltstones adjacent to, and potentially concealed by, the Mount Dore Granite.

Marilyn

The Marilyn prospect is located 800 m to the east of Mount Dore. Trenching and shallow drilling by previous companies intersected widespread copper oxides (e.g. MAAT-19: 10 m @ 0.3% Cu from surface; MAAT-10: 4 m @ 1% Cu from 16 m). Four diamond holes tested beneath previous shallow intersections and tested a controlled source audio-frequency magnetotellurics (CSAMT) anomaly at depth. The drilling intersected narrow zones of weak copper, gold and zinc mineralisation hosted in phyllite and emplaced along the contact between granite and black shale. Widespread weak copper and zinc sulphides, and abundant disseminated to massive pyrite and pyrrhotite, appear to have provided the source of the Marilyn CSAMT anomaly. A much deeper conductive body from natural source audio-frequency magnetotellurics (NSAMT) beneath the granite remains to be tested.

Ballarae

The Ballarae prospect is located 800 m south of Mount Dore, and is characterised by widespread surface copper mineralisation, including chalcocite, and a weak molybdenum rock-chip anomaly. Three diamond holes totalling 786 m were drilled and intersected widespread weak copper and gold mineralisation, hosted in black shales, but no significant molybdenum intercepts.

Flora

At Flora, located 1 km north of Mount Dore, six diamond holes were drilled to test beneath extensive surface copper mineralisation. Drilling on the northern extension of Merlin tested 300 m downdip of this intercept and intersected widespread polymetallic copper-gold-lead-zinc mineralisation.

Busker

The Busker prospect 700 m north of Merlin is characterised by surface copper and molybdenite mineralisation and a strong CSAMT anomaly at depth. One hole was drilled in order to test the CSAMT anomaly, which appears to have been sourced from weak copper mineralisation hosted within the thrust contact of Mount Dore Granite and the underlying metasediments.

Flora East

At Flora East, deep magnetic and CSAMT features possibly represent a deep-seated IOCG system located beneath the Mount Dore Granite. The presence of trace chalcopyrite and magnetite hosted within the Mount Dore granite updip of the Flora East prospect indicates that there is also potential for granite-hosted copper mineralisation. A detailed ground magnetic survey was used to resolve the depth and geometry of several targets. A NSAMT survey, which will lead to better resolution of the deep CSAMT features, is planned.

Cave Hill

The largest surface copper and molybdenite anomalies discovered to date along the Mount Dore Belt are located 3 km to the north of Merlin at the Cave Hill prospect. Drilling has intersected widespread weak copper mineralisation hosted in the same brecciated black shale horizon as Mount Dore. Below this copper horizon, at the same horizon occupied by Merlin, hole MRR0001 intersected 22 m @ 0.19% Mo and 0.18% Cu from 131 m, including 3 m @ 0.94% Mo from 131 m; and 1 m @ 1.82% Mo from 141 m. Hole MRR0002a, located 400 m north of MRR0001, intersected 0.27 m @ 2.3% Mo from 129 m. A detailed structural geology study is underway to define the controls of molybdenum mineralisation along the Mount Dore Belt.

Metal Ridge

The Metal Ridge group of prospects (including the Metal Ridge, Metal Ridge North and Metal Ridge West prospects) is located approximately 4 km east of Amethyst Castle and approximately 10 km north of the Starra series of IOCG deposits. It is more broadly located within the highly prospective Mount Dore fault zone which hosts a number of diverse styles of mineralisation. The Mount Dore deposit contains significant secondary oxide and sulphide copper mineralisation that was delineated by previous operators in a copper soil geochemical anomaly about 1.5 km long and over 400 m wide; more importantly it contains the Merlin molybdenum and rhenium deposit. This geochemical anomaly is associated with 1.5 km long magnetic and conductivity anomalies. The Metal Ridge North target extends south towards a major magnetic feature at the Metal Ridge prospect which has not yet been fully tested by Ivanhoe Australia. A well defined CSAMT anomaly has also not yet been fully tested.

The favourable host rock, the fluid chemistry and extent of alteration in close association with a major regional structure indicate the Metal Ridge area is highly prospective. This oxide style of mineralisation can be traced sporadically along strike to the Metal Ridge prospect, a distance of approximately 6 km. This entire belt has been the centre of extensive shallow prospecting since the early 1900s in response to the numerous outcrops of high-grade copper. A termite mound geochemistry survey tested 579 mounds and various copper, molybdenum and uranium anomalies were identified for follow-up. These results were similar and coincident to soil geochemistry surveys carried out by previous operators.

The Metal Ridge prospect is located 5 km to the north of Mount Dore, and is defined by a strong, 200 m wide and 2.5 km long soil, rock--chip and termite mound copper anomaly. Like Cave Hill, this anomaly is associated with gossanous breccias and brecciated black shales located along the thrust margin of the Mount Dore Granite. Limited drilling has intercepted wide zones of weak copper mineralisation hosted in the same black shale horizon as at Cave Hill and Mount Dore

The Metal Ridge North prospect is located 6 km north of Mount Dore. Drilling has targeted the downdip extensions to earlier intercepts and a coincident CSAMT anomaly. The holes intersected narrow zones of weak copper mineralisation, hosted in phyllite, but no significant intersections. Abundant pyrite and pyrrhotite appear to have provided the source of the Metal Ridge North CSAMT anomaly. Several mineralised breccias remain undrilled at the prospect.

Mount Cobalt

This area, which lies within a granted ML and is the site of an historical cobalt mine (estimated production to 1938 of 20,000 tonnes at 4% Co), is situated approximately 4 km southeast of the 222 Starra deposit. The copper, gold, cobalt and rare earth mineralisation is hosted within a shear zone at the margins of an amphibolite. Drilling along strike in 2010 intercepted copper-gold-cobalt mineralisation; including an intercept of 17 m @ 0.41% Cu, 0.5 g/t Au, 596 ppm Co and 0.4% TREE.

Victoria

The Victoria deposit, situated approximately 12 km south of Mount Dore, has been previously mined for high-grade copper oxide as supplemental feed in Starra flotation plant in two open pits. The deposit is similar in character to the Mount Dore deposit, hosted in brecciated shale and siltstone in proximity to the major thrust west of the Yellow Waterhole Granite. During 2008, three diamond drill holes targeted potential depth and strike extensions. This drilling tested the sulphide zone and intersected sporadic chalcopyrite and very minor molybdenite.

THE ELANA M TREND AND THE KURIDALA AREA

Much of the regional exploration within the Ivanhoe tenements has been focused on the Elana M Trend, an 8 km long structural trend approximately 50 km north of the Merlin deposit. The Elana M Trend consists of six prospects which host significant copper, gold, molybdenum and rhenium mineralisation. Of these prospects the Lanham's Shaft, Barnes Shaft and Triga prospects were drilled during 2009 and 2010 and all have retuned significant results (Figure 2).

Barnes Shaft

Barnes Shaft copper-gold mineralisation occurs within altered and brecciated calc-silicates and carbonaceous metapelites of the Corella/Doherty Formation between two east-northeast trending faults. Chalcopyrite is the dominant copper-gold bearing mineral with some chalcocite in shallower intercepts. A Sub-Audio Magnetic (SAM) survey highlighted a greater than 1 km long conductivity anomaly coincident with current mineralised drill intercepts.

Ivanhoe Australia commenced an aggressive drill program at Barnes Shaft in 2010 after reconnaissance drill holes intersected moderately anomalous copper-gold over moderate widths from surface including 28 m @ 1.01% Cu and 0.6 g/t Au from 10 m in RC hole BAR0001. The subsequent drill program has included 21 diamond and 19 RC holes defining a north-northwest trending zone of anomalous copper, gold and cobalt 300 m long and 100 m wide open to the north and downdip to the east. Significant intercepts include 12 m @ 2.17% Cu, 1.14 g/t Au and 438 ppm Co from 14 m in BAD0001, and 33 m @ 1.12% Cu, 0.6 g/t Au and 378 ppm Co from 28 m in BAD0006. This drilling indicates mineralisation occurs as several parallel bodies dipping at approximately 60 degrees to the southeast. To date, five sections have been completed and mineralisation can be linked between these sections.

More recently, deeper drilling has highlighted significant potential at Barnes Shaft for high-grade mineralisation. Drill Hole BAD0018 returned assay results of:

BAD00018- 29m @ 3.21% Cu, 3.37g/t Au and 383 ppm Co from 210m
and- 27m @ 3.40% Cu , 3.60g/t Au and 403 ppm Co from 211m
inc - 1m @ 10.05% Cu, 13.35g/t Au and 800ppm Co from 223m


These are some of the most significant Cu-Au-Co drill results received from regional exploration drilling within Ivanhoe Australia's tenements. Continuing drilling around this intercept is targeted at extending the high-grade zone and determining grade continuity between it and other significant zones above and along strike.


Figure 2: Historic intercepts on the Elana M Trend


Lanham's Shaft

Lanham's Shaft is located on the northern end of the Elana M Trend. Mineralisation (Cu-Au ± Mo and U) is concentrated in a breccia-fracture zone adjacent to the contact between black shale and calc-silicate, with alteration similar to that at Mount Elliott. Molybdenum mineralisation and associated uranium occur typically in late-stage, northwest trending, calcite-chlorite matrix breccias and veins hosted in calc-silicates. A SAM survey shows the deposit lies on a conductivity high (shale/structure/mineralisation related) over 1 km long.

Drilling at the Lanham's Shaft prospect has confirmed the discovery of a second molybdenite system.



Triga

The Triga prospect located at the southern end of the Elana M Trend is hosted in black shales with previous drilling by several companies identifying strong copper, gold and molybdenum mineralisation at shallow depths.

Drilling during 2009 totalled four RC and two diamond holes. Significant results were TRRC0011 returning 58 m @ 0.87% Cu, 0.68 g/t Au and 0.09% Co from 8 m including 22 m @ 1.59% Cu, 0.53 g/t Au and 0.12% Co. A deeper intercept from the same drill hole returned 30 m @ 0.89% Cu, 0.18 g/t Au and 326 ppm Co from 124 m including 14 m @ 1.39% Cu, 0.32 g/t Au and 389 ppm Co. These results included 0.34% Co for one 2 m intercept. Follow-up diamond drilling will be conducted to assess the strike and depth extent of this mineralisation.

Kuridala

The historic Hampden Kilometre area, located 30 km north of Mount Elliott, is the site of the historical Kuridala group of mine workings which lie within Ivanhoe Australia's tenement EPM 9116. A mining lease in the name of Matrix Metals Limited, and now controlled by QMC, covers the Hampton Kilometre mine area to a depth of 100 m and below this depth the mineral rights belong to Ivanhoe Australia.

Previous drilling by Arimco and others intersected high-grade copper-gold bearing sulphide mineralisation below 100 m depth in the vicinity of previously mined out stopes of the Hampden Kilometre mine. This work indicated the mineralisation occurred as discontinuous shoots in intensely deformed metasediments. Best results from earlier drilling below the old stopes in the Ivanhoe Australia owned tenement included 51 m @ 3.8% Cu and 1.64 g/t Au in CON001 and 43 m @ 2.22% Cu + 0.87 g/t Au in CON003 , while the best result from later drilling was 33.8 m @ 3.03% Cu and 1.38 g/t Au in KRCD-96-3. The zone remains open at depth down plunge to the south where there is limited drilling.

Straight Eight

The Straight Eight prospect, located 4 km east of Kuridala, consists of shallow copper oxides grading to breccia and vein-hosted chalcopyrite within brecciated and altered black shale and phyllite of the Kuridala Formation. Mineralisation has developed along and adjacent to the northwest trending Straight Eight Fault. Drilling in 2008 (16 holes; 2,998 m) encountered mineralisation and alteration that was generally weak but similar to that at the SWAN zone of Mount Elliott with significant intercepts including, but not limited to 34 m @ 0.66% Cu and 0.15 g/t Au from S8R0085; including 20 m @ 0.92% Cu and 0.2 g/t Au.

Diva

Drilling at the Diva group of prospects returned significant results. Eleven RC holes and a single diamond hole were drilled into a group of four prospects approximately 4 km northwest of the Mount Elliott deposit. These drill holes targeted Mount Elliott style mineralisation and encountered numerous anomalous to moderate-grade intercepts of copper and gold.

EXPLORATION TARGETS IN THE CENTRAL AREA

Northern Gossans


The Northern Gossans are located northwest of Mount Elliott. The geological setting is similar to the Corbould zone at Mount Elliott as strongly anomalous copper and gold is associated with an ironstone outcrop

Central and Northern Leases

For at least a further 1.5 km along strike to the northwest of the Northern Gossans zone, further sporadic copper and gold anomalism has been indicated by soil sampling and shallow airtrac drilling at the Central Leases and Northern Leases prospects, as well as limited diamond drilling in 2009.

Reindeers

Three previously defined prospects, Rudolph, Donner and Blitzen, are located in a group approximately 20 km northwest of Starra in an area with generally similar underlying geology to the Western Ironstones. Airborne magnetic surveys show a positive north-south trending anomaly, interpreted as the sub-outcropping, folded continuation of the Western (Starra) Ironstones. Gold-only mineralisation occurs at Blitzen proximal to subcropping ironstones with anomalous copper-gold mineralisation at Donner.

Previously shallow, wide-spaced drilling between the three prospects intersected anomalous copper and gold. Previous drilling focussed at Blitzen and Donner has intersected 30 m @ 5.56 g/t Au from 32 m in BLRC-20, including 6 m @ 25.5 g/t Au from 44 m. A small gold only resource defined at Blitzen by previous owners is being re-evaluated for processing at the Osborne plant CIP circuit.

Amethyst Castle

Reconnaissance drilling conducted in 2006 by Ivanhoe Australia at the Amethyst Castle prospect, located approximately 9 km southwest of Mount Elliott, encountered significant intersections of IOCG-style breccias containing gold and copper mineralisation with related uranium. These encouraging intersections, and more importantly the intensity and style of the breccia-hosted mineralisation, demonstrate the potential for a large-scale system. Ivanhoe Australia has identified further drill targets at Amethyst Castle using recent IP and gravity surveys. The future exploration program for Amethyst Castle will involve diamond drilling of these targets along with geophysical studies to identify further targets.

Slate Ridge

Slate Ridge, approximately 14 km west of Starra, consists of near-surface gold-only oxide mineralisation and deeper copper-gold oxide, supergene and primary sulphide mineralisation. Mineralisation occurs as infill of steeply dipping brecciated quartz veins and within graphitic and gouged shear zones. Detailed soil surveys by previous owners identified strongly anomalous gold and copper in soils extending 2 km along strike south of previous drilling. Rock-chip analyses confirmed high-grade copper and gold at the surface.

Previous drilling comprised 46 holes; significant intercepts included, but are not limited to 102 m @ 1.12% Cu and 0.70 g/t Au (from 22 m; SRRC-07) and 72 m @ 1.75% Cu and 0.64 g/t Au (from 56 m; SRRC-26). Ivanhoe Australia is awaiting assay results from four diamond drill holes completed in October 2010, including strong, narrow (<1 m) massive chalcocite and chalcopyrite intersections.

A small gold-copper resource was published over Slate Ridge by previous owners. Ivanhoe Australia is reviewing this resource and drilling extensions for potential upside following the purchase of the Osborne plant.

URANIUM PROSPECTS

Uranium was first targeted within Ivanhoe Australia's Cloncurry Project tenements in the late 1960s and mid-1970s, with work carried out at the Elizabeth Anne, Mariposa, Utah and Mount Dore uranium/copper prospects by Marathon Oil and Minerals Pty Ltd (Marathon Oil) and separately by Amoco Minerals. Uranium was also discovered at the Dairy Bore, Old Fence, U2 and Robert Heg prospects by Rio Tinto/CRA in the Kuridala area, now the northern part of Ivanhoe Australia's tenements.

In November 2006, Ivanhoe Australia commissioned three airborne magnetic and radiometric surveys over areas within the northern and central tenements of the Cloncurry Project; and in 2010 a further survey was flown to infill the remainder of the central part of the tenement package. The initial two surveys were flown specifically for uranium exploration and generated numerous substantial uranium anomalies.

Utilising the results from these radiometric surveys, Ivanhoe Australia identified priority uranium exploration targets within the Kuridala area. The priority prospects included the Robert Heg, Dairy Bore/Old Fence, Elizabeth Anne, Great Wall, Farley and Triga prospects.

Ivanhoe Australia has reviewed the work undertaken by the previous workers and has undertaken limited drilling on all of these targets, except Farley, with limited success. Amethyst Castle described earlier remains a high priority IOCG and uranium target

A summary of the Kuridala area prospects follows.

Robert Heg

Robert Heg is the most advanced uranium-dominant prospect within the Cloncurry Project. Early exploration work by Rio Tinto/CRA at Robert Heg included 18 drill holes that defined a high-grade uranium zone over an area of 150 m x 100 m with ore grade intersections, as in Table 2.

Table 2 Robert Heg Assay Results from CRA (cut-off 120 ppm U)

Drill Hole

Interval (m)

From (m)

Grade(U3O8) ppm

Grade1, 2 (ppm U)

RH1

22

13

4,810

4,079

includes

11

14

9,346

7,925

RH 23

3

6

354

300

RH33

3

8

251

213

RH43

2

10

153

130

RH5

14

4

173

147

RH6

6

4

153

130

RH7

10

70

1,644

1,394

includes

6

72

2,358

2,000

RH9

16

4

395

335

and

22

38

1,985

1,683

includes

4

36

9,434

8,000

RH13

16

24

665

564

includes

4

30

2,081

1,765

RH14

10

6

354

300

and

10

70

278

236

RH15

10

6

354

300

and

10

70

278

236

RH16

44

14

353

299

includes

2

40

1,910

1,620

1. Grades rounded to nearest 10ppm 2. Intercepts may contain intervals of up to 2m of less than 0.01% U. Holes RH 2, 3, and 4 were abandoned at shallow depth due to collar collapse.

Follow-up Ivanhoe drilling is shown in the following table of drilling results based on a 100 ppm U cut off:

Table 3 Selected Ivanhoe Australia uranium exploration results at Robert Heg (cut-off 100ppm U)

Drill Hole

Interval (m)

From (m)

Grade(U3O8) ppm

Grade (ppm U)

RHDD0019

11

15

3,590

3044

includes

9

15

4,304

3650

RHDD0020

2

32

908

770

and

9

283

473

401

RHDD0021

24

64

224

190

includes

2

67

837

710

RHDD0022

5

239

590

500

includes

1

240

2,005

1700

RHDD0023

2

152

200

170

RHDD0024

8

10

195

165

and

2

166

814

690



Dairy Bore - Old Fence

Dairy Bore contains two prospects known as DB1, located 3 km west of Kuridala, and DB2, located 1 km southeast of DB1. An air core drilling program has been completed over this prospect and has returned promising results Anomalous base and precious metals occur at Dairy Bore in addition to uranium. Soil sampling by Rio Tinto returned up to 70 ppm U at DB2.

Old Fence is located along the same regional fault as Dairy Bore and 5 km southwest of Kuridala (3 km southeast of DB1). Old Fence was previously explored by Rio Tinto for copper (not uranium), with RC drilling yielding intersections including one of 18 m at 0.38% Cu. Ivanhoe identified a strong positive uranium anomaly during a regional radiometric survey, prompting increased focus on uranium exploration.

Drilling by Ivanhoe in 2010 did not intercept significant uranium mineralisation.

U2

At U2, located 2 km south of Robert Heg and 12 km southeast of Kuridala, two magnetic anomalies are associated with a local granite contact. The sole assay sample is a single rock-chip (Marathon Petroleum) of approximately 4% U. Limited drilling by Ivanhoe did not intercept significant uranium mineralisation.

U3

U3 is one of Ivanhoe Australia's main uranium targets and comprises the Elizabeth Anne, Great Wall and Torbernite Trench prospects. Ivanhoe Australia mapped and sampled the ironstones at Torbernite Trench. One hole drilled at Torbernite Trench intersected a 2.8 m thick magnetite-altered zone with trace chalcopyrite and molybdenite but no promising uranium mineralisation.

Elizabeth Anne, 8.2 km southeast of Kuridala at the southern extension of the Straight Eight Fault, was initially identified by Frio Mining Pty Ltd and subsequently surveyed and then drilled by Marathon Petroleum with 56 percussion and three diamond holes. Twenty of the holes had intervals of greater than 500 ppm U3O8 with the best result being 1.6 m @ 7200 ppm U3O8. Assay results from a sample of granite taken from this area achieved 4.29% U3O8. Secondary copper was also identified at this prospect. Ivanhoe Australia drilled two diamond holes downdip of historic trenches returning up to 4 m @ 261 ppm U from 62 m in U3D0003a and 4 m @ 112 ppm U from 79 m in U3D0004.

The Great Wall prospect, 1 km south of Elizabeth Anne and identified by airborne radiometric analysis is the southern folded extension of the Elizabeth Anne ironstone. Ivanhoe Australia's field inspection at Great Wall identified secondary uranium minerals within siliceous ironstone. A drill hole in the Great Wall area targeted the ironstone fold nose. The hole encountered trace chalcopyrite and molybdenite but no promising uranium mineralisation.

Other Prospects

Apart from the targets outlined above, previous exploration within the Cloncurry Project area has identified over 250 prospects that represent targets for future exploration. While many of these prospects are currently on the low priority list for Ivanhoe Australia, many represent genuine and potentially significant exploration opportunities for the future.  
Disclaimer and Privacy Policy