it AUSIMM COBAR MINING SEMINAR

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1 Straits Resources Limited it AUSIMM COBAR MINING SEMINAR Brownfields Exploration at Girilambone: Understanding the Mineralised Systems August 2010 Phil Shields / Phil Jones

2 LOCATION TRITTON OPERATIONS Located 15km north of Hermidale. 100% Straits Resources Ltd 1757km 2 tenement area (4 EL s and 3 ML s) Active exploration program Drilling 20,000m 000m / year $6M/year exploration expenditure on the leases TRITTON LOCATION PLAN

3 REGIONAL GEOLOGY Girilambone Group Ordivician in age Thick Turbidite sequence of greywackes, pelites and psammopelite lithologies Associated with mafic volcanics, volcaniclastics and intrusive mafics Low grade metamorphism Greenschist Facies Strong alteration (Si + Ser + Py + Chl) extending from Budgery Tritton Girilambone Strong deformational overprint Strong NW trending faults TRITTON REGIONAL GEOLOGY JOHN CROSSING (2010)

4 MINERALISATION Besshi style exhalitive deposits - synchronous with deposition Low grade Cu Zn systems Banded sulphide zones with massive lenses Predominantly pyrite with lesser chalcopyrite, sphalerite and trace gold. Copper grades averaging 1 3%, Zinc grades averaging % Complex ore mineralogy includes magnetite, galena, tetrahedrite tennantite, pyrrhotite. Lithological and structural control on mineralisation Poor metal zoning grade distribution TTDD002: MASSIVE Py + Cpy

5 BESSHI DEPOSITS Besshi Deposits worldwide; Deposits range in size from < 1Mt to 300Mt Besshi (Japan) 2.5% Cu, 0.3% Zn, 0.2 g/t Au Windy Craggy (Canada) 1.8% Cu, 0.2g/t Au Soucy (Canada) 1.4% Cu, 1.1% Zn, 2g/t Au Brittania (Canada) 1.9%Cu, 0.7% Zn, 0.7g/t Au Ducktown (USA) 1.0% Cu, 0.9% Zn

6 DEPOSIT GEOMETRY Tabular, stratiform bodies with good depth extensions (Tritton tested to 1500m below surface) Consistent dip of the deposits (30 o 50 o )SE Strike lengths typically averaging m Multiple sheets Tritton / Budgerygar & North East / Double Tanks TRITTON / BUDGERYGAR DEPOSITS

7 TRITTON MINE Tritton Deposit: Underground copper mine discovered in 1995 Development to 680m below surface 2009 Resource: 2.3% Cu 2009 Reserve: 2.2% Cu 2009/10 Production: Concentrate: 81,182t Contained Copper: 20,226t TRITTON DEPOSIT

8 TRITTON MINE Deep drilling below Tritton Mineralisation extends >1400m below surface Mineralisation increasing i in thickness and grade TTDD005W intersected 1.46% Cu, including 6.0% Cu Significant folding resulting in a high grade hinge zone open at depth. Further drilling planned for 2010 / 11. TRITTON DEEPS HOLE INTERCEPTS

9 TRITTON MINE Observations; Significant advances in understanding the stratigraphy with marker horizons including Black Siltstone, Quartz rich Psammite, H/W and F/W Dolerites and volcaniclastics Soft sediment breccias containing sulphide clasts, mafic / ultramafic clasts and various host fine grained sediment clasts above the deposit DPI involvement to help with whole rock geochemistry of mafic units, various isotope studies for dating of the mineralisation and fluid inclusion studies Alteration consistent with a hydrothermal exhalitive system with a chloritic F/W and an ankerite rich H/W Petrology showing sulphides synchronous with sedimentation

10 BUDGERY BUDGERY MINE: Located 5km NW of Hermidale Historical workings discovered in 1905 Small scale leaching precipitation it ti on steel Previously drilled to a depth of 150m defining a small oxide / transitional resource Banded sulphides sheet with massive lenses Two zones (Upper and Lower) dipping at 40 o SE Strike length 200m with the top of mineralisation 10m below surface BUDGERY DEPOSIT

11 BUDGERY Scoping study completed for a small open cut operation Resource: 1.1% Cu 21,500t contained copper metal 2 3 year mine life Good underground potential for significant sulphides at depth Banded sulphides are up to 40m thick but pyritic. BUDGERY MAGNETICS & PROPOSED PIT

12 BUDGERY Supergene profile capping the deposit Oxide (malachite / azurite // cuprite) 0 to 70m Transitional (chalcocite) 70 to 150m SCHEMATIC CROSS SECTION BUDGERY DEPOSIT

13 MURRAWOMBIE Murrawombie deposit situated 2km west of Girilambone Oxide open cut completed in 1997 Initial development two levels below the base of the pit. Banded sulphide zone with similar characteristics to the Tritton orebody Strong structural overprint with localised graphitic shearing Good depth potential drilled to a depth of 650m below surface MURRAWOMBIE 5050 LEVEL 10N

14 MURRAWOMBIE Murrawombie Resource: 1.6% Cu (0.8% Cu cutoff) MURRAWOMBIE BLOCK MODEL

15 MURRAWOMBIE MTD054 - exhalitive layered siliceous sulphidic sediment: Upper Massive Sulphide Horizon MTD054 Thinly interbedded quartz rich pelite and carbonaceous pelite in H/W to massive sulphide: Weak Graphitic

16 GIRILAMBONE NORTH Girilambone North deposits 25km NE of Tritton Sulphide potential below existing oxide pits Previous small scale historical workings in the area Current underground operation at the North East deposit Exploration underway to drill test depth extensions to North East and Larsens GIRILAMBONE NORTH PITS

17 GIRILAMBONE NORTH North East resource: 2.3%Cu (40,000t contained copper) GIRILAMBONE NORTH CONCEPTUAL MINE PLAN

18 FUTURE WORK Understanding the stratigraphic sequence of activity within the formation and interpreting this zone throughout the tenements Elemental analysis on the mafic volcanics and comparison between the deposits Continuing identification of markers within the sequence Follow up the origin of sulphide clasts within soft sediment breccias above the Tritton orebody Structural t study to understand d the spatial relationship of high h grade copper zones and folding within the deposit Deep drilling below the known deposits to extend the mineralised system