Geology and mineralisation of the Mewet Vein, Jelai Gold Project ...

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PT GMT Indonesia Mewet Vein : Jelai Gold Project 12 INTERPRETATION AND CONCLUSIONS The Jelai Gold Project contains known precious metal mineralisation in a number of north-south trending low-sulphidation epithermal vein structures. Drill testing of these veins by two companies has resulted in a certain confidence that parts of the mineralisation can be geologically modelled, as the data density is sufficient to undertake such an exercise. The first area chosen for the geological modelling of the mineralisation is in the Mewet Vein area, concentrated on a section of the vein that has been drilled in some detail. The Mewet Vein crops out on the side of a small, north-south trending, ridge. The vein consists of small discontinuous outcrops of colloform banded chalcedony with adularia in the drilled area. Sections of the vein structures predominately consist of volcanic clasts and are commonly set within a calcite matrix which breaks down easily resulting in a subdued topographic expression. The veins or breccias do not form prominent topographic features in any part of the system. Weathered breccia outcrops may have a box-work appearance due to the leaching of the volcanic clasts. The mineralisation in the Mewet vein comprises a discrete lode structure containing mixed hydrothermal vein breccia, massive quartz veins and colloform-crustiform quartz veins in a zone trending generally north-south and dipping at approximately 60° to the west Over the strike length of the vein a pinch and swell effect is observed with the width being variable at a similar RL along the strike of the vein. The lode dips at approximately 60° with a late cross-cutting quartz-carbonate vein and fracture fill phase at 65-70°. Late phase veins are typified by glassy to milky, fine grained drusy quartz + carbonate which are generally barren with assays rarely exceeding 0.02 ppm Au. The late phase quartz is rarely weakly amethystine in nature and crosscuts all phases of brecciation and veining. High gold values were obtained from finely banded, colloform-crustiform, quartz-adularia veins. The highest gold values occur in zones of multiphase brecciation of the colloform banded quartz which are healed by chalcedonic quartz and adularia. No gold mineralisation occurs in the footwall to the vein but low grade gold values occur within the breccia on the hanging wall to the quartz vein. Silver grades are sporadic with the most elevated values occurring with the high grade gold in finely banded, sulphidic, quartz veins. The assessment of data has outlined an exploration target of between 900,000-950,000 tonnes of mineralisation with a gold grade of approximately 3 g/t and an accompanying silver grade of approximately 3 g/t. This calculation cannot be defined as a resource at this stage and should be considered as an exploration target only. The programme of exploration conducted by JCM has successfully outlined a number of areas of coherent mineralisation in the Jelai Gold Project area, of which one example is the Mewet Vein. The initial aims of the programme have been met, that is, to define the vein structures in the near surface environment and prepare targets for deeper drilling. 0065 JCM/GEO/2009.04 Page 38
PT GMT Indonesia Mewet Vein : Jelai Gold Project 13 RECOMMENDATIONS The following recommendations are made for the ongoing work programme at the Jelai Gold Project: 1. The area has demonstrated sufficient data to attempt a resource modelling study on certain segments of some of the better defined veins. 2. The addition of data in the Mewet Vein area would raise the confidence of the geological model and the management of some issues, such as poor core recovery in some drill holes, will give greater confidence to the grade model generated. 3. Other areas where consistent mineralisation has been outlined should also be assessed for continuity and a geological model updated to include the other areas, such as the Sembawang Vein area and the Lipan Vein. The modelling of the geology should not only outline areas of mineralisation but also quantify areas of the geological model and data set that requires further input and clarification. 4. A more concerted drilling effort is required in outlining areas around the main project, which have structural and alteration characteristics similar to the Mewet Vein and Sembawang Vein areas, and, 5. Re-categorise the exploration target to comply with the reporting standards as required by the 43-101 guidelines. The following specific recommendations are made: 1. The drill hole spacing should be closed to 25 metre pierce points along the main Mewet Vein area modelled, this includes drilling on sections 356,475N, 356,425N and 356,350N where drill holes are required below the shallow scout drill holes, 2. Deep drilling on section 356,500N, below JCM-067 to test the plunging shoot to the north on the vein structure and extending at the same level one section north again to 356,575N below hole number JCM-074, 3. Manage the core recovery position on all drilling by using larger diameter core where possible (requiring a larger drill rig), with HQ core size recommended as the recovery was good in the previous Ivanhoe drilling using this core size, 4. Future drilling should include routine standards and blanks (5% of total samples) in the dispatch stream and check analyses should be conducted at an alternate laboratory, 5. A complete and comprehensive survey of drill collars is required and downhole surveys at 30 metre intervals is recommended for future drilling. 13.1 Future Work Programmes To advance the knowledge of the Jelai Gold Project, it will be necessary to conduct further drilling in the known vein areas and regional exploration in peripheral targets. The mineralisation in the project area is extensive and a number of targets are yet to be tested by drilling and a number of other targets have only had preliminary reconnaissance mapping completed over them. The recommended work programme budget is shown in Table 9. Work Programme Duration Units Estimated Budget (USD) Regional geological mapping and sampling 6 months $ 75,000.00 Scout drilling peripheral targets and new vein areas 9 months 4,000 metres $ 500,000.00 Resource drilling Mewet / Sembawang Vein 6 months 5,000 metres $ 1,000,000.00 Analytical work 9 months 2,500 samples $ 70,000.00 0065 JCM/GEO/2009.04 Page 39
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