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| | EritreaOverviewSanu's largest exploration program is targeting copper+zinc+precious metal-rich volcanic-hosted massive sulfide (VHMS) mineralization in Eritrea, East Africa. Eritrea is emerging as one of the most important new VHMS camps in the world with significant new discoveries by Sunridge Gold in the central highlands (Debarwa, Adi Nefas and Emba Derho) and Nevsun Resources (Bisha, Bisha NW, Harena) and Sanu (Hambok) in the western lowlands. VHMS deposits frequently occur in clusters with a number of significant deposits occurring in a belt. An example is the Iberian Pyrite Belt of Spain and Portugal which hosts 88 deposits with an aggregate 1.6 billion tonnes of massive sulfide containing 63 million tonnes of zinc+copper+lead. While there is no guarantee that the Western Eritrea will be as prolific as the Iberian Pyrite belt,, it remains one of the largest and most under-explored VHMS terranes in the world and the company believes the potential for multiple major discoveries is high. Our extensive ground position, experienced prospecting team and the recent high discovery rate in the belt with four discoveries in five years, suggests that prospects for exploration success are excellent. Sanu began exploring in Eritrea in 1998 and already has one major VHMS discovery in its Hambok deposit. At present Sanu's exploration licenses cover 1080 square kilometers of and over 100km of strike length of prospective ground in the western belt that also hosts Nevsun's Bisha deposit (22 Mt at 1.8% copper, 3.78% zinc, 2.08 g/t gold, 42 g/t silver). The project area is located 200 km west of the capital city of Asmara and is accessible year round by road. The Hambok Deposit, discovered in March, 2006 and located 15 kilometres to the southwest of the Bisha deposit extends for 1000 meters along strike and over 300 meters down dip and is 10-50 meters thick. The Hambok deposit is open in several directions and the prospective host geology with its associated gravity and EM anomalies extend for several kilometers along strike. Sanu is actively exploring for extensions and satellites of the Hambok deposit as well as identifying new VHMS prospects on its ground. Location Sanu's projects are located in the western lowlands of Eritrea approximately 200km by road west of the capital city of Asmara. Sanu's land position covers approximately 100km of favorable stratigraphy northwest and southeast of Nevsun's Bisha Deposit. Ownership Sanu holds its exploration ground through exploration licenses granted by the Eritrean government. The government retains a 10% carried interest in all discoveries and has the right to acquire an additional, fully-contributing, participatory interest in any discovery. Geology/Mineralization Volcanic-hosted massive sulfide (VHMS) mineralization in western Eritrea occurs in Neo-proterozoic volcanic arc rocks that are part of the granite-greenstone terranes of the Arabian-Nubian shield. Similar geological environments host major polymetallic VHMS mining camps in Canada, Spain and Portugal, Japan and Australia., The volcanic arc rocks of the Arabian-Nubian shield underly western Saudi Arabia, southeastern Sudan, northern Ethiopia, and most of Eritrea. To date all massive sulfide discoveries in Eritrea have been copper and zinc rich. The near-surface, oxidized portions of the massive sulfide deposits are often strongly enriched in gold and in some instances have been mined as stand alone deposits in the Ariab district of Sudan and in Saudi Arabia. Both Ariab and Bisha contain more than one million ounces of gold within 50m of the surface. Maps (click to enlarge)
Sanu's Hambok Deposit was discovered by Landsat TM imagery analysis and reconnaissance geological mapping and soil sampling which led geologists to a low hill of siliceous ferruginous breccia and a nearby, thin 50cm to 3m wide gossan outcrop. Follow-up mapping outlined a train of gossan float more than 400 meters long adjacent to the siliceous breccia in intensely chlorite-altered bimodal metavolcanics. Gravity surveys defined a strong 1.2 milligal anomaly centered some 700m south of the outcropping gossans, which, on drilling, was found to coincide with the main massive sulfide body. A strong 'maxmin' EM anomaly adjacent to the gravity anomaly helped define the dip of the drill target. Drilling of 13,244m in 61 holes has identified a steeply east dipping Cu and Zn mineralized massive sulfide body extending for 1050m on strike length and over 300m down-dip. The thicker sections of the massive sulfide system (> 50m) also contain the higher grade portionsof the deposit and appear to lie in a zone 500m long. Mineralized drill intercepts in the central part of the massive sulfide body include 18m of 1.05% copper and 5.90% zinc. The mineralization at Hambok shows excellent continuity and uniformity of grade, permitting outlining of the resource at wide drill spacing and low cost. Detailed mapping, geochemical sampling, and geophysical surveys around Hambok are defining targets that may be stacked, fold repeated, or satellite bodies that could add to the existing resource. Several such targets will be drilled in the coming year. Maps (click to enlarge)
The Company has started a new drilling campaign on newly discovered prospects on trend with the Company's Hambok VMS copper/zinc deposit in western Eritrea. The initial program has been budgeted for 2000m of diamond drilling with plans to add drilling to immediately follow up any encouraging results. The program is expected to be complete before the start of the summer rainy season at the end of June. The current drill campaign will test conductors identified by recently completed ground EM and gravity surveys which were run along strike from the Hambok deposit. Hambok is a significant massive sulfide body measuring approximately 1000m long by 300m down dip by 10-50m thick. The results of the geophysical surveys show a number of strong EM conductors coincident with the strike extension of the Hambok stratigraphy and a strong structural trend ("the Hambok trend") that is visible on regional gravity maps. Recent trenching through alluvium on the "Hambok trend" in the Aderat area located approximately 4.5km north of Hambok, revealed two gossan horizons approximately 3-5 meters thick hosted within a chlorite and hematite altered felsic tuff that is approximately 30 meters thick. The subcropping gossans dip to the west and are on the flank of a broad gravity high which currently cannot be explained by local topography or lithology. Gravity highs are coincident with massive sulfide mineralization at Hambok and Nevsun Resources' nearby Bisha Deposit. The initial phase of the drill program will target the Aderat gossan horizon and associated EM anomaly as well as other EM anomalies and gravity highs along the "Hambok trend". The remainder of the drill program will test a number of significant new gossan discoveries in the northern part of Sanu's exploration license. Exploration The Company has intersected a new volcanic hosted massive sulfide (VHMS) zone on its Aderat prospect 4.5km north of its Hambok Cu-Zn deposit. The 571m of diamond core drilled at Aderat to date are part of a larger drill program to test the "Hambok trend", a significant geophysical feature defined by anomalous gravity and EM, and geology. Assay results are pending and will be reported as soon as they are available. The mineralization at Aderat is blind, buried beneath 2 to 3m of alluvium in flat terrain and was discovered through a trenching program based on extrapolating prospective geological trends into this area. DDH ANK-005 was targeted to test the projection, at depth, of gossanous horizons, an EM conductor, and adjacent to a gravity high on the Hambok gravity trend 4.5kms north of the Hambok Cu-Zn sulfide body. The drill hole intersected two narrow gossan horizons near the top of the hole and two bands of banded massive to semi-massive sulfides, 3.0m and 8.0m wide respectively, with traces of chalcopyrite and sphalerite deeper in the hole. The sulfide bands are within a 57m section of sericite and chlorite altered sulfidic felsic tuffs. ANK-006 was also targeted to test the projection, at depth, of gossanous horizons and a strong EM conductor adjacent to a gravity high. ANK-006 intersected two zones of massive to semi-massive pyrite-sphalerite-chalcopyrite mineralization, 5m and 12m respectively within a larger 90m envelope of strongly altered felsic tuff with disseminated pyrite with traces of sphalerite. The 12m zone, deeper in the hole, is within a 28m zone of sphalerite and chalcopyrite mineralized pyritic tuff. The presence of zinc and copper was confirmed by field XRF analysis but definitive grades are being confirmed by conventional assay techniques. ANK-007, drilled approximately 100m underneath ANK -- 006, encountered only disseminated pyrite mineralization in rocks interpreted as the hanging wall of the sulfide horizon. The Aderat VHMS-style mineralization is open along strike to the northeast and southwest of the ANK-005 and 006 intersections. Drilling will resume at Aderat after the completion of testing of the "Hambok trend" and other targets on the Mogoraib River and Kerkebet River Exploration Licenses. Maps (click to enlarge)
Prospecting and target development work including geological mapping, geochemical sampling, gravity surveys and satellite imagery analysis continued through the year and has now covered most of the license areas. The objective of this work was to identify additional targets for drilling, particularly in areas of thin alluvial cover. During this program field crews discovered a new zone of VHMS occurrences at Koken in the northern part of the Kerkebeit license area. This is the first discovery of volcanic hosted massive sulfide (VHMS) mineralization in the area and potentially constitutes an entirely new district. The gossan occurrences crop out over a strike length of 4.5km with the individual gossan zones up to 11m wide in outcrop and up to 400m long. Zones of massive barite mineralization up to 5m wide as well as disseminated barite in gossan occur toward the northern end of the trend. Koken Prospect Rock chip analyses of more than 80 gossan outcrop samples from the Koken trend returned strongly anomalous values in gold, copper, zinc, and lead in the majority of samples, with peak assay values of 36.9g/t for gold, 4337 ppm copper, 6101 ppm zinc and 5633 ppm lead. The rock samples cover the Koken prospect strike length of approximately 4.5km. (see detailed map). The geochemical results from the Koken gossans show similarities with the gold-bearing gossan of Nevsun's Bisha deposit and also to those being mined for gold in the Ariab district in the Sudan. The Koken gossans occur in a sequence of metamorphosed dominantly felsic bimodal volcanic rocks that are coincident with a Landsat image analysis anomaly, shown in green on the attached map. The Landsat anomaly appears to be tracking hydrothermal alteration associated with the mineralized gossan outcrops. The prospect area lies on the west limb of a north plunging syncline. Early stage prospecting and mapping on the east limb, 4 km to the northeast, and on a parallel structure 2kms to the north has found rocks, alteration, and new gossan outcrops similar to those at Koken. Preliminary sampling results from the gossans also show anomalous Cu, Au, and Zn content. Drilling of nine reconnaissance diamond core holes is underway on the Koken prospect and is expected to be completed before the end of this field season in early July. The Company also drilled several other prospects on the Mogoraib license in western Eritrea. The most encouraging results were obtained from Ashelli where eight diamond drill holes tested a gossan and siliceous horizon where surface soil sampling had identified an anomalous zone of oxide copper and gold mineralization as well as disseminated and stratiform sulfide mineralization. Significant intersections at Ashelli include 22m of 1.93g/t Au, 2m of 1,048 g/t Ag, and 3m at 3.07g/t Au, all in oxide material. Additional work will determine if there is potential for a thicker sulfide body at Ashelli, either along strike, or as a structurally repeated body. Maps (click to enlarge)
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