The Prospect Hill Tin Deposit; New Discoveries and Ideas

Transcription

1 The Prospect Hill Tin Deposit; New Discoveries and Ideas SAEMC December 2014 Graham S. Teale Adrian M. Brewer C. Mark Fanning Havilah Resources NL

2 Acknowledgments Much of the new data for this presentation was gathered by the authors during the current exploration joint venture with Havilah Resources NL. Historic data obtained during exploration work by the authors for numerous other companies, from 1982 until the joint venture with Havilah Resources NL in 2007, has also been drawn upon. The authors would like to thank Havilah Resources NL for permission to give this presentation.

3 Competent Persons Statement The information in this presentation that relates to Exploration Targets, Exploration Results and Mineral Resources is based on data compiled by geologists, Graham Teale and Adrian Brewer, who are Competent Persons and who are members of The Australian Institute of Geoscientists. Both Graham Teale and Adrian Brewer have sufficient experience, which is relevant to the style of mineralisation and type of deposit and activities described herein to qualify as a Competent Person as defined in the 2012 Edition of Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves. Messrs Teale and Brewer consent to the inclusion in the presentation of the matters based on their information in the form and context in which it appears. This information was prepared and first disclosed under the JORC Code It has not been updated since to comply with the JORC Code 2012 on the basis that the information has not materially changed since it was last reported.

4 Prospect Hill Mount Babbage Inlier Mount Painter Inlier C U R N A M O N A 31 L ak e Fr om e P R O V I N C E Cainozoic & Mesozoic Adelaidean and Cambrian sediments Willyama Supergroup 32 OLARY DOMAIN BROKEN HILL DOMAIN Broken Hill Km Olary Source : PIRSA ( a MESA) PROSPECT HILL - Northern Flinders Ranges, S.A

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6 Geology Mineralisation discovered in South Ridge Deposit contains an Indicated Resource of 302, % Sn to 90 metres vertical depth. Additional lodes continue to be located. Mineralisation (South Ridge) open at depth on the western end (PHRCO37, 0.85% Sn) and eastern end (PHRCO29, 0.48% Sn). Samples >1% Sn can be located for an additional 400m west of the last drill-hole on the South Ridge. No deep drilling. The Prospect Hill Domain, including the South Ridge, Fly Hill and Central Ridge mineralisation is highly sheared, in part mylonitic, and trends approximately EW. Mineralisation is pre-tectonic.

7 Mineralisation is contained within metamorphosed and highly deformed Mesoproterozoic pyroclastics that have been dated at 1560 ± 2Ma (Sheard et. al., 1993) Some quartz-rich sediments and epiclastics are intercalated with the felsic pyroclastics and possible felsic domes. Numerous granitic/porphyry stocks High level, A-type sub-volcanic intrusives emplaced into the pyroclastics. These intrusives are enriched in Pb, Zn, F, U and Sn and have been dated at 1552Ma Reprocessing of magnetic data indicates that the Mesoproterozoic basement is most likely shallow underneath the Cretaceous and recent cover suggesting potential for further discovery

8 A major structure separates this distinct terrain from the Mesoproterozoic terrain to the south. The Prospect Hill Granite porphyry and the White Well Granite only occur to the north of this structure. The structure separates deep rapakivitic granites (~1555Ma) from high level porphyry intrusives (1552Ma) The Prospect Hill area contains the youngest Mesoproterozoic terrain within the Mount Painter Province and the Curnamona Craton in general Recent soil and portable XRF data indicate that South Ridge mineralisation continues for ~400m to the west (up to 3878ppm Sn in soils)

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10 Significant Tin Intersections Southern Ridge Prospect PHP % PHRC % PHP % PHRC % PHP % PHRC % PHP % PHRC % PHP % PHRC % PHRC % PHRC % PHRC %

11 Former quartz phenocryst in deformed and metamorphosed pyroclastic Note the garnet in the bottom RH corner. PHRC06-55m-56m Quartz-veining and magnetite development at Fly Hill. Sample contains 0.2% Sn Sample Mag. x 50; length of photomicrograph = 2.6mm; PPL recrystallised quartz vein Mag. x 20; scale bar = 500µ; PPL

12 The meta-volcanics were altered prior to deformation and contain high SiO 2 (76-78%), low Al 2 O 3 (~11%), negligible CaO, Na 2 O and MgO, high Y (~80ppm), Zn (~500ppm), Sn (~30ppm) and W (15-30ppm) Two different volcanic units are present, the northern meta-volcanics and the southern meta-volcanics. The latter are more enriched in tin. The meta-volcanics are enriched in the REE and exhibit marked LREE enrichment and a pronounced negative Eu anomaly

13 (Sheard et. al., 1993)

14 High Level Intrusives Intrusives dominated by quartz-k-feldspar-sodic plagioclase-biotite; abundant fluorite and accessory zircon, monazite, apatite, tourmaline and rare uraninite and cassiterite. The biotite, although Fe-rich, contains high F. The Prospect Hill Granite porphyry contains ~72.5% SiO 2, ~12% Al 2 O 3, ~6.7% K 2 O, 0.52% F and high Y (130ppm), U (50ppm), Rb (550ppm), Th (175ppm), Pb (65ppm) and Sn (20ppm). The White Well Granite exhibits granophyric textures and is also high level. It contains ~76% SiO 2, 11.7% Al 2 O 3, negligible MnO, CaO and MgO, ~6% K 2 O and high Y (~120ppm), Th (~55ppm) and Pb (~55ppm).

15 Prospect Hill Granite Porphyry. Note the large ovoidal phenocrysts and rounded tourmaline aggregates

16 PROSPECT HILL GRANITE PORPHYRY

17 (Sheard et. al., 1993)

18 1000 Mineralisation Sample / Chondrite 100 Mineralisation Prospect Hill Granite Footwall volcanic La Ce Nd Sm Eu Gd Dy Er Yb

19 Tertiary, Quaternary (Cainozoic) sediments and alluvium Adelaidean (Neoproterozoic) Fitton and Bolla Bollana Formations Adelaidean meta-quartzite & conglomerate. Shanahan Conglomerate equivalent Reworked silicic volcanics Northern silicic meta volcanics Southern silicic meta volcanics and epiclastics Prospect Hill Granite Porphyry Whitewell Granite Terrapinna Granite Mineralised zones Prospect Hill 217.6m N 173 Faults Vertical schistosity (S1) Plunge of minor F1 folds PROSPECT HILL Geology and Stream Sediment Geochemistry Modified after Hodkinson, 1982 and Teale, m White Well Bore Stream Sediment Geochemistry Sample site >70 W : ppm >32 >500 >100 >40 Sn : ppm

20 Sn mineralisation; quartz-cassiterite-biotite-muscovite, South Ridge Zn biotite cassiterite Mag. x 100; length of photomicrograph = 1.3mm; PPL PHRC03 44m-45m

21 Sn mineralisation; quartz-biotite-gahnite-garnet (-cassiterite), South Ridge garnet gahnite Mag. x 50; length of photomicrograph = 2.6mm; PPL PHRC03 45m-46m

22 Sn mineralisation; garnet-cassiterite-margarite-muscovite, South Ridge F-margarite garnet cassiterite Mag. x 100; length of photomicrograph = 1.3mm; PPL PHRC04 35m-36m

23 Footwall; muscovite-magnetite-gahnite-garnet developed as groundmass to large corroded quartz phenocrysts. Here gahnite rims fine grained magnetite. South Ridge gahnite magnetite Mag. x 200; length of photomicrograph = 0.65mm; PPL PHRC05 35m-36m

24 Scheelite contained within quartz veins cutting high grade Sn mineralisation cassiterite scheelite Mag. x 50; scale bar = 200μ; PPL PH32

25 Highly sheared fluorite-quartz-muscovite-cassiterite rock, South Ridge fluorite Sample Mag. x 20; scale bar = 500µ; PPL fluorite Mag. x 20; scale bar = 500µ; crossed nicols

26 Gangue South Ridge Major: quartz, fluorite, biotite, Mn-Ca-rich garnet, muscovite Minor: gahnite, F-rich margarite, tourmaline, magnetite, sulphides (sphalerite, galena, chalcopyrite, tetrahedrite) Trace: zincian chlorite, Zn-rich magnetite, apatite, epidote Location of Tin Cassiterite (no stannite present) Maximum concentrations of tin in other minerals are: biotite % Sn epidote % Sn spinel % Sn garnet % Sn These concentrations are rare however.

27 The Fly Hill lode contains grab samples grading up to 34% Sn and has been traced using a portable XRF unit for approximately 300m. It has been cut by faulting at its western end. It appears to be zoned with anomalous Mo-Cu developing laterally to the Sn(-Cu) mineralisation. Anomalous W-Cu develops adjacent to the Mo-Cu with cuprotungstite found along shear planes. Fly Hill mineralisation is fine grained (~10-40µ) and intimately associated with tourmaline. The cassiterite is developed within strongly sheared and deformed volcanics and quartz breccias. Central Ridge mineralisation tends to be associated with quartz, tourmaline and muscovite. Coarse grained and up to 2mm in size

28 Cuprotungstite developed along shear fabric

29 Fly Hill, cassiterite-rich milled breccia

30 Massive cassiterite associated with quartz, muscovite and quartz, Fly Hill lode cassiterite sericite tourmaline Mag. x 50; scale bar = 200µ; PPL Sample 20017

31 Quartz-cassiterite breccia developed between large quartz phenocrysts, Fly Hill Sample Quartz and lithic fragments in cassiterite matrix breccia, Fly Hill Sample Mag. x 20; scale bar = 500µ; PPL Mag. x 20; scale bar = 500µ; PPL

32 Cassiterite veining cutting quartz-cassiterite-tourmaline mineralisation, Fly Hill Mag. x 200; scale bar = 50µ; PPL Sample 20011

33 Cassiterite cementing quartz grains, Central Ridge area Sample 20022A Coarse grained cassiterite associated with quartz, Central Ridge area Sample 20022A Mag. x 20; scale bar = 500µ; PPL Mag. x 50; scale bar = 200µ; PPL

34 Origin of Tin Mineralisation Mineralisation has developed in intensely altered felsic pyroclastics. Alteration occurred during the emplacement of the sub-volcanic intrusives Cassiterite is associated with minor Pb-Zn-Ag sulphides and contains anomalous Bi, Sb, In, Se, Cu, Te, As, U, Cd and W along the South Ridge Mineralisation is sulphur-poor with only minor Fe-sulphides (pyrrhotite). Zn also contained in spinels, oxides and silicates and trace Pb contained in epidote. No gossans and missed by early Cornish miners

35 Mineralisation (South Ridge) contains abundant fluorite, gahnite, Mn-Ca-rich garnet, zincian biotite and F-rich margarite (calcic mica). Cassiterite-quartz breccias at Fly Hill and coarse grained tourmaline-bearing tin assemblages at Central Ridge Mineralisation is not Cambro-Ordovician and shares a similar age to host volcanics and intrusives Previous interpretations such as beach placer, Delamerian vein, volcanic exhalative and BHT equivalent are not correct Mineralisation shares similar REE patterns to host volcanics and sub-volcanic intrusives. It developed via the movement of Sn and metal-bearing fluids from a sub-volcanic porphyry body similar to the Prospect Hill granite porphyry

36 Pb Isotope Data - Prospect Hill and other areas; Fanning and Teale, Carr

37 Pb/ 204 Pb Pb/ 204 Pb Pb Isotope Data, Palaeozoic Mineralisation; Brewer and Teale

38 Summary Tin mineralisation occurs over a wide area. Mineralisation has been tested on the Southern Ridge with an Indicated Resource of 302, % Sn present to 90 vertical metres depth. The mineralisation is open at depth to the west (PHRC %) and to the east (PHRC %). 400m of lode as yet untested. The Fly Hill lode is approximately 300m in length and contains apparent boudins of extreme grade (~34% Sn). These boudins can be tens of centimetres to tens of metres in length and are dominated by quartz-cassiterite breccias

39 Mineralisation on the South Ridge is associated with intensely altered pyroclastics and contains minor sulphides and abundant fluorite, Mn-Ca-rich garnet, gahnite, biotite (often zincian), quartz, magnetite (often zincian) and K and Ca-rich micas. Scheelite usually develops in late veins cutting the tin mineralisation Elsewhere mineralisation is associated with similar deformed Sn and U-rich A-type volcanics and sub-volcanic intrusives which were extruded and emplaced at ~1555Ma. The intrusives are extremely enriched in F, Y, U, Rb, Th, Pb and Sn These may be the youngest volcanics and intrusives in the Curnamona Craton

40 The limited Pb-isotope data are similar to Pb-isotope data from the North Portia/ Kalkaroo mineralisation dated at ~1600Ma Alluvial/eluvial Sn potential and U potential in adjacent Tertiary/Cretaceous sequences has not been tested Intrusives similar to the Prospect Hill Granite porphyry and the White Well Granite and their associated skarn mineralisation may develop along the northern flanks of the Curnamona Craton and along the eastern flank of the Gawler Craton