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Tierra De Oro Project

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.

 

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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.