Pelangan Gold Prospect

Updated: 110711

The Pelangan Gold Prospect is located approximately 1.5 hours' drive on good roads from Nusa Tenggara Barat's capital, Mataram. The prospect is located at the northwest end of a 13-km long, northwest-trending structural corridor of mineralization and alteration within which also lie the Selodong copper-gold porphyry prospect at the south end and the Mencanggah epithermal/porphyry district in the centre of the corridor. Both of these prospects are also targets of Southern Arc's on-going exploration of the West Lombok Property.

The Pelangan Gold Prospect includes at least five large and complex quartz vein systems: the Raja, Kayu Putih, Ratu, Tanjung-Jati and Lala veins. The previously unknown unknown Lala Vein was discovered by Southern Arc in June 2006, and with on-going detailed DGPS mapping new MSB structures are being identified within the prospect. An aggressive diamond drilling program is currently under way with five rigs operating. These are testing the North Raja area and the Tanjung lode below Phase 1 drill hole TDG002, and at the Central Raja lode and on South Raja. Phase 2 drilling results are encouraging with excellent gold grades being returned and at least one 6.15-m interval returning a bonanza grade of 37.7 g/t Au and 26 g/t Ag.

Drilling at the Pelangan Gold Prospect

A shallow scout, 50-hole Phase 1 drilling program (Phase 1 drilling program) was completed by Southern Arc in the first quarter of 2007 on the the Raja, Kayu Putih, Ratu, and Tanjung-Jati veins (see various Pelangan Gold Prospects maps). Southern Arc's geologists apply the field nomenclature "Mineralized Structural Breccias", or MSBs, to these epithermal vein targets. Surface mapping and the Phase 1 shallow drilling have indicated more than 5 km aggregate strike length of outcropping MSB-type gold mineralization, together with high-grade gold-silver ore shoots.

The Pelangan Gold prospect is open to the south and east, where additional mineralized breccias have been identified and surface exploration, mapping and geochemical sampling is on-going. The presence of high-grade shoots are suggested by a high-grade quartz episode within the MSBs (steeply-dipping silica ledges cut by epithermal quartz veins and breccias) and increasing gold grade with depth, as indicated by the on-going Phase 2 drilling. 

The second phase, two-stage drilling program at Pelangan was originally started in August 2008, with Phase 2.1 focused on the central part of the Raja MSB. The Raja vein represents less than 10 percent of strike length established to date for Pelangan alone. This drilling program is designed to target high-grade gold-silver shoots along the 1 km strike zone at central (400 m long) and south Raja (600 m long) as well as test for down-dip continuity of mineralization, sustained vein widths and depth extensions along with other undrilled targets that show high-grade surface results.

Upon the completion of the first two Phase 2 holes, PLD001 and PLD002, there was a temporary hiatus to the drilling program until certain legal aspects related to permitting of mining activities on Lombok were resolved by the provinical government and the IUP for the property was subsequently granted to Southern Arc.

The Phase 2 drilling intercepts show continuity of mineralization over widely spaced intervals with the localized development of high-grade shoot zones. The program at Pelangan is on track to test all the mineralised structures at wide  intervals to detect potential shoots within the structure. More closely spaced in-filling drilling will then focus on these shoots. To date potential high-grade shoots remain open at depth and along strike at Central Raja and the latest results indicate excellent potential for the South Raja Lode.

Recent Work

At the end of February 2011, three diamond drill rigs were mobilized to Pelangan to resume the Phase 2 drilling program. Subsequently two more were added in late June. Delayed by heavy and unseasonal rainfall, Phase 2 drilling was able to commence again on March 27. As at June 28, a total of 18 holes have been completed, including PLD001 and PLD002, of which assay results are pending for four of the holes and with five other holes currently in progress.

The drilling rigs are situated to target the MSB on adjacent sections along strike. Infill drilling between the initial fences will be determined by assessment of results as drilling progresses, with additional rigs to be mobilized as warranted throughout the drilling program.

Phase 2.1 is planned to be drilled within the 400-m long high-grade part of the central Raja MSB between QDG04 and RDG07, which were drilled during the first phase drilling program in 2006 to 2007. Four Phase 2.1 drill fences are located so to test the down-dip mineralized extensions of RDG01, RDG04, RDG05 and RDG07. As drilling progresses geology and assay data will be wire-framed and modeled in Micromine to derive a compliant resource estimate.

The first three of the five rigs are testing for high-grade ore shoots at the central Raja target in the prospect. The drill rigs are capable of coring to depths of greater than 400 m, which is adequate for the scope of this drilling program as this stage of drilling is testing for MSB mineralization at depths of 300 to 350 m. At least 15,000 m of Phase 2 and infill resource drilling will be carried out to fast-track to a NI 43-101 compliant resource status.

Phase 2.2 comprises at least six drill holes to cover a total strike length of 600 m between QDG006 and RDG012 of the south Raja MSB. Five Phase 2.2 drill holes are also planned to test below and in between Phase 1 high-grade shallow intercepts at Kayu Putih for a total strike length of 670 m to be drilled.

All Phase 2 drill holes to date have intersected MSB epithermal mineralization and have confirmed that high-grade epithermal gold mineralization remains open beyond 250 m depth below surface.

Phase 2 drilling results are as follows:

PLD003 intersected high-grade mineralisation over 250 m vertically below surface and 100 m below the high-grade intersection of PLD002, thus confirming the depth potential at Pelangan. The mineralisation in this area is exposed at the surface and remains open at depths exceeding 250 m. PLD003 was drilled in the same cross-section/vertical plane as drill holes RGD01, PLD001  and PLD002.

Drillholes PLD004 and PLD006 were completed on a section/vertical plane 150 m southeast of PLD003 down dip from the Phase 1 drill hole RDG04. These holes intersected MSBs at 75 m and 115 m below surface, respectively.

PLD005 intersected two narrow zones of mineralization approximately 200 m northwest of PLD003.

PLD007 was drilled on a section 105 m NW along the structure from drill holes PLD001, PLD002 and PLD003. PLD007 intersected mineralization over 100 m vertically below the surface. Its substantial width highlights the potential for high-grade "blow-outs" or swells within ore shoots in the MSB structures. These have the potential to host significant high-grade tonnage.

PLD008 intersected MSB mineralisation 50 m southeast of drill holes PLD001, PLD002 and PLD003, approximately 90 m below surface and returned these two broad mineralised intervals.

PLD009 was drilled 80 m SE of PLD007 and at a slightly lower elevation.

PLD010 was drilled on the same section as PLD008 and intersected quartz veining approximately 80 m below PLD008. The PLD010 intersection confirms good continuity of mineralization at depth vertically below PLD008 as well as onto the adjacent section 40 m to the northwest where PLD002 intersected 17.25 m @ 5.73 g/t Au & 11.7 g/t Ag (see below).

Drill hole PLD011 returned a broad intersection of mineralization.

PLD011 was drilled on the same section as PLD003, intersecting the mineralised structural breccia 40 m higher on section. The hole was drilled to infill the gap between PLD002 and PLD003. It was also to confirm the previously reported PLD003 intersection, which had encountered very broken ground. It was felt that core loss in this interval could have compromised the validity of the sampling. However, the result from PLD011 confirms the integrity of the interval in PLD003 and also the consistency in the breccia thickness and grade over a 120 m vertical interval between PLD002 and PLD003.

Drill hole PLD012 intersected two lower grades of mineralization.

The two mineralized zones intersected exhibit intense post-mineral shearing or faulting with abundant clay fault-gouge disrupting the mineralized structural breccia and may indicate a major 'pinch' or fault off-setting within the breccias' extent.  The drill hole was positioned on the same section and 105 m below PLD007. Though lower-grade, the result proves continuity in the structure well below PLD007.

Drill hole PLD013 returned a wide zone of lower grade mineralization.

PLD013 tested between PLD008 to the northwest and PLD006 to the southeast. The interval confirms continuity of the mineralized structural breccia development in this part of the Central Raja lode.

Drill hole PLD014 returned a broad mineralized interval.

PLD014 tested mineralisation 75 m below RDG005 (22.95 m @4.1 g/t Au & 17 g/t Ag). This intersection is highly encouraging as it is the first deeper hole drilled in the South Raja Lode. PLD014's position at the northern extremity of this lode leaves open a big area for potential high-grade shoot development at depth and for at least 500 m strike extent to the southeast.

Previous Work

The first Phase 2 hole to be drilled at Pelangan, PLD001 on the central Raja Vein, was started on August 23, 2008 and completed on September 4 at a length of 150 m. Hole number PLD002 was subsequently started on the same day at the same location, but drilled at a steeper angle to test the vein at greater depth. It was completed on September 24 at a length of 221.8 m.

These first two Phase 2 drill holes returned very encouraging results on all three objectives, intersected the gold-bearing epithermal breccia zone at depth below the earlier Phase 1 drillhole RDG01. RDG01 had returned an intersection of 10.70 m @ 2.93 g/t Au, including 4.70 m @ 5.80 g/t Au. The two Phase 2 holes targeted depths of 60m and 120 m below the RDG01 interval.

These first two Phase 2 holes intersected the following mineralized intercepts:

Drill hole PLD001          4.85 m @7.11 g/t Au and 18.5 g/t Ag from 56.55 m
               including         1.35 m @ 16.67 g/t Au and 17.0 g/t Ag from 56.55

Drill hole PLD002         17.25 m @ 5.74 g/t Au and 11.7 g/t Ag from 121.60 m
               including          8.75 m @ 10.51 g/t Au and 20.7 g/t Ag

Phase 2.2 drilling is justified because the results from Phase 1 drilling and the first two Phase 2 holes support the concept of increasing gold grade with depth in Central Raja and confirm the existence of high-grade ore shoots within the system, thus highlighting the need for further extensive deeper drilling at Pelangan. Drilling has identified a "bonanza" episode within the Central Raja MSBs, characterized by significantly higher gold-tenor, generally greater than 10 g/t, low silver/gold ratios, and specific vein textures. Such bonanza episodes can localize within the vein zone to form high-grade ore shoots, which can add significant ounces to a deposit within relatively small areas. 

Crucial detailed DGPS mapping and topographic surveying at Pelangan, which commenced in mid-October 2008, continues to be carried out. DGPS mapping was carried out within the Lala, Mendorot and Raja MSB areas. The Lala MSBs are traceable over several hundreds of metres. Mapping at Mendorot has revealed a 700 m long MSB, with further mapping extending the MSBs southeastward sub-parallel to the Lala East MSB as far as Montong Bagik. Earlier mapping over the western slopes of Batu Sendi and west Pelangan has identified an additional 500 m of western extension to the Jati MSB and a possible southwest extension to Kayu Putih. A new MSB, Paluh Tangi, approximately 700 m west of Tangjung-Jati, has been mapped. Geochemical sampling of these new MSB zones will be completed at a later time.

Surface prospecting for associated blind porphyry Cu-Au targets is also under way at Pelangan. Clay soil samples are being taken for 'Hychip' PIMA analyses for the identification of potential high-temperature clay species relevant for porphyry vectoring.

Early recognition of ore-shoot controls such as structural intersections, favourable host lithologies and distribution of high-grade surface material will aid in determining the three-dimensional geometry and hence the targeting of bonanza-events within the MSBs. Southern Arc is using this information to aggressively target and define potential ore-shoots with the aim of quickly developing gold resources at Pelangan.

See Pelangan Phase 2 Drilling & Assay Statistics Summary

See Raja MSB Target Longitudinal Section

Phase 1 Drilling

See Pelangan 2006 – 2007 Phase 1 Drilling Program and Previous Work