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

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Mewet Vein : Jelai Gold Project
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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