The highly prospective
project, which comprises 49.34 square kilometres, covers a
historic gold camp and lies within the same intrusive/volcanic
sequence that hosts several large open pit gold and copper/gold
mines.
The gold camp at "Tierra de Oro"
is reported to have produced several hundred thousand ounces
of gold from surface workings prior to the 1930's and is now
considered a strong prospect for the development of a large,
bulk tonnage, open pit type deposit.
The property is accessed by well maintained
gravel roads and is located 20 km from the Pan American highway,
next to the main Chile power grid. With a maximum elevation
of only 1,500 meters the region enjoys good climactic conditions
for year round exploration.
For the team of seasoned professionals
at International PBX, exploration results to date have provided
strong indications that the "Tierra de Oro" will
ensure the company's long term future success in Latin America's
most prestigious mining nation.
Click to view Property Compilation
Map
Geological, geochemical and geophysical
exploration programs to date have evaluated, at least at a
semi-detailed scale, approximately 50 of the 70 sq. km encompassed
by the "Tierra de Oro" Project. Within this
area, thirteen large gold and copper-silver target zones have
been discovered. The first phase, 3,000 metre reconnaissance
reverse circulation drill program partially tested five of
these zones, three of which returned results worthy of follow
up programs.
A)
GOLD ZONES
1. Fe-Skarn Zone - is
currently a 600 x 1600 metre area of coincident high soil
gold and copper values and IP anomalies encompassing numerous
old surface and underground vein workings plus extensive placers.
Trenching of one part of this zone has returned gold values
up to 2.2 gpt over 42 metres width. Drilling 200 metres along
strike from the trench intersected 15 metres of 1.9 gpt gold
at 85 metres vertical depth below surface chip sample values
averaging 2.7 gpt gold over 13 metres width. This sub-zone
can be traced via scattered outcrop and old workings for at
least 500 metres in either strike direction from the area
of drilling. The zone at large can be traced at least a kilometre
to the northeastwhere a 25 metre section of 27 gpt gold has
been found, and may merge with the Bella Ester Zone one kilometre
to the Southwest. More extensive drilling and trenching is
required to evaluate the full potential of this extensive
area of mineralization.
2. Central Gold Zone - is a 500 x
1500 metre area of high gold soil values and IP anomalies
also encompassing numerous old vein workings assaying up to
16.4 gpt gold over several metres width. These workings are
grouped in several north to northeast elongate sub-zones sub-parallel
to dyke swarms. The worked veins are multi-directional and
along with finer intervening veinlets form auriferous stockworks
100 to 200 metres wide and 300 to 500 metres long. During
the next phase of exploration, additional detailed surface
work and drilling will be focused on several of these strong
auriferous stockworks.
3. Bella Ester Zone - is 200 x 1000
metre area of high soil gold and copper values encompassing
old workings on a gold bearing manto horizon grading up to
2.43 gpt over 6 metres. The soil anomaly contains gold values
up to 10.2 gpt. Additional surface work and drilling is also
planned to test this zone during the next phase of exploration.
4. Chanchero Zone - is a 1000 x 2000
metre area of partially coincident high gold and copper values,
which overlies an equally large area of gold and copper bearing,
porphyry style alteration. Assays from old workings and outcrop
range from 0.5 to 16.7 gpt. The soil anomaly and known mineralization
are included within a larger strong IP anomaly. Several holes
were drilled in this zone during the first drill program.
Two were lost due to heavy water inflow before reaching their
targets. The third, on the north edge of the system, cut disseminated
pyrite and trace chalcopyrite in propylitically altered intrusives.
There still remains sufficient room in the system to host
a deposit of several hundred million tonnes.
5.
Inca Gold Zone - is a 100 to 400 metre wide, 1200 metre
long, northerly trending zone of strong argillic alteration
and auriferous quartz veining which crosscuts the northeast
end of the Chanchero Zone. Extensive vein workings occur throughout
the zone. Several have been mined to depths of over 75 metres
and strikes of several hundred metres. Gold assays from these
veins consistently grade 4 to 7 gpt over widths of 1 to 2
metres. The only trench crossing the zone returned 1.1 gpt
over 114 metres and terminated in 2.2 gpt material on the
west side. This zone requires additional trenching and drilling
as the next phase of exploration.
B) COPPER ZONES
1. Las Lomitas Zone -
is a 700 to 1600 x 3000 metre arcuate zone of high copper
± silver soil values overlying altered andesitic fragmentals
on the flanks of a 12 km long dome with a dioritic intrusive
core. Numerous oxide Cu workings on stratabound mantos and
sub-vertical structure zones are present throughout the zone.
Assays from these workings consistently average 0.5 to 2.5%
Cu over 2 to 30 m widths. The surface oxide mineralization is partly
underlain by a large IP anomaly, which suggests a deeper intrusive
related sulphide source. Several holes drilled on the edge
of this chargeability anomaly intersected disseminated chalcopyrite
and pyrite in propyplitically altered andesites and diorite
porphyry dykes. The core of the zone remains to be tested
in future phases of exploration.
2. Cobalt Horizon - is a 100 - 400 x 2500 metre copper-in-soil
high throughout which are mineralized outcrops of altered
andesite breccia. Assays from the southwestern half of the
horizon range from 1 to 4.5% copper, 10 to 220 gpt silver
and 0.02 to 0.2% cobalt. Two shallow holes were drilled in
the first phase program to test a strong chargeability high
at the southwest end of the zone. Extensive disseminated and
vein chalcopyrite and pyrite associated with a silicified
diorite porphyry sill was intersected over widths of 30 to
50 metres. Two stronger zones of copper mineralization are
indicated by the assays, the upper ranges from 7 metres of
0.56% copper plus 10.3 gpt silver to 8 metres of 0.47% copper
plus 14.0 gpt silver. The lower (cobalt) zone was intersected
in only one hole and graded 0.37%copper, 0.27% cobalt and
14.3 gpt silver. Additional surface work and drilling is required
to test the remaining 2.3 kilometres of this zone.
3. North Contact Zone - is a 100 to
200 metre wide, 1500-metre long copper soil anomaly located
at the intersection of the intrusive-volcanic contact and
series of strong northwest trending structures. Limited exploitation
has taken place in a number of trenches and pits scattered
along 400 meters of strike length. Mineralization is exposed
on both sides of the pediment cover and could be substantially
wider beneath it. Samples from the principle workings on this
zone returned average values of 1.7% copper with 7 gpt silver
over 3 metres width. Additional detailed surface work followed
by drilling is required to fully evaluate this zone.
4. San Juan - This zone of copper-silver
mineralization is located in an area close to the intrusive-volcanic
contact along strike to the northeast of the Northern Contact
Zone but a higher stratigraphic level. Oxide copper mineralization
has been mined here from one large pit in a bedded cherty
limestone and limy siltstone sequence. Mineralization is dominantly
stratabound within this unit and occurs as disseminations
and fracture coatings. Although mined at only one spot, test
pits and rusty mineralized outcrop cover an area of at least
0.75 sq. km. Rock chip assays from the pit average 1.5% copper
and 44.3 gpt silver over the accessible 6 metres of the 10
metre mined width. This zone to date has only been outlined
by prospecting and requires detailed geological, geochemical
and geophysical surveys to confirm its significance.
5. Teresa Zone - this 4 sq kilometre
area of oxide copper-silver workings occurs on the axis of
the Lomitas anticline six kilometres northeast of the Lomitas
Zone. Numerous old workings on multi-directional mineralized
structures and mantos occur throughout the zone in massive,
epidotised and vesicular andesites. The andesites contain
the most extensive workings wherein grades of 2 to 3% copper
over 3 to 5 metre widths are found where copper oxides fill
the vesicles in the andesites. As with San Juan, this zone
to date has only been outlined by prospecting and requires
the same detailed follow up surveys.
In
conclusion the size significance of the target zones defined
to date cannot be overstated. Any one of the gold zones is
more than big enough to host a million-ounce deposit. Similarly,
the surface extent of the copper-silver zones is more that
sufficient to enclose near surface oxide deposits of 10 to
20 million tonnes. In addition, several have the larger potential
of underlying sulphide sources of several hundred million
tonnes.
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