Vancouver —
The 80-sq.-km property is 70 km north of the Pascua and Veladero gold deposits of
Satellite imagery has identified a large colour anomaly that represents hydrothermal alteration patterns and a large southeast-trending structure that spans both properties.
The reconnaissance work has outlined two priority targets. The first of these comprises 3 sq. km and is defined by strongly anomalous values in both gold and copper, assayed from rock and stream-sediment samples. Surface grab samples returned up to 1.45% copper and 1.89 grams gold per tonne.
The geological setting, a high-sulphidation epithermal environment, is similar to that being drill-tested by the Tenke-Rio Tinto joint venture, a few kilometres to the north.
The second target is represented by a prominent colour anomaly on satellite imagery; it measures 1.5 km across and is situated on the western part of the property. Alteration and mineralization styles suggest that it may represent a copper-gold porphyry target. Initial rock and chip sampling returned anomalous values in molybdenum, copper and gold within an extensive zone of clay alteration.
The Mogote property is a joint venture between IMA and Rio Tinto, with the latter retaining an option to earn up to a 70% interest. Rio Tinto must spend US$1.85 million on exploration over the next three years to earn a 51% interest in the property. An additional 19% can be earned by funding a further US$7 million in work prior to the eighth anniversary of the agreement. All further costs will be will be shared on a pro rata basis.
Meanwhile, IMA has discovered another gold target on the Tamborapa property in northwestern Peru. Dubbed Las Minas, the target is 1.2 km southeast of the Cerro Tablon area.
The company can acquire a 100% interest in the 90-sq.-km property, which lies between 1,200 and 2,200 metres above sea level. The village of Tamborapa (population 800) lies at the edge of the property and is accessible by road.
IMA believes that the extensive area of altered rocks (in excess of 1 sq. km), combined with anomalous sampling results, represents an excellent target for a bulk-mineable gold-silver target.
The Cerro Las Minas target is hosted by felsic tuff and agglomerate with widespread zones of silicification and argillic alteration similar to the upper portions of many mineralized epithermal systems, including the Veladero and Yanacocha deposits. Mineralization in the area consists of a core of volcanic-hosted, disseminated gold mineralization with high-grade structurally controlled quartz veins on the periphery.
Results from a soil geochemistry program over a 700-by-300-metre area indicate a strong gold anomaly. The average of 91 samples returned 0.32 gram gold, the background gold-in-soil values are typically 0.04 gram gold, and the anomaly remains open in three directions.
In addition to the main anomaly, reconnaissance soil sampling to the east returned a strong gold anomaly. Twenty soil samples taken over 400 metres returned an average of 0.9 gram gold per tonne, the range being 0.02-to-2.61 grams. This anomaly remains open to the north and south.
A second phase of work will include ground and airborne geophysics, as well as sampling and mapping.
Reconnaissance work last year identified a large boulder field in the valley between Cerro Tablon and Cerro Las Minas, which contained sulphide-rich boulders of up to 600 tonnes. The company chip-sampled 22 of these boulders and returned an average of 9.3 grams gold, ranging from 0.07 to 30.1 grams gold, as well as strongly anomalous values of silver, copper and zinc.
Sampling of the outcrops and near-in-situ slabs of rock returned up to 57.7 grams gold. The average assay of 112 rock samples was 3.59 grams gold. Follow-up sampling returned up to 26.5 grams gold from limited areas of outcrop and colonial-age workings.
Mineralization at Cerro Tablon is said to be associated with altered limestones adjacent to an intrusive contact. An additional target, Cerro Tablon West, lies 1 km southwest of the main Tablon prospect. Limited rock sampling there has returned up to 1.1 grams gold associated with anomalous copper, zinc and bismuth.
Meanwhile, IMA continues to define drill targets at its Rio de la Taguas and Potrerillos properties in northwestern Argentina.
In May 2000, IMA completed an initial 9-hole program of reverse-circulation drilling on the Fabiana zone, part of Potrerillos, which is 5 km east of the Veladero joint venture of Barrick and Homestake Mining.
Six of the holes intersected several narrow intervals, with anomalous gold values of up to 1.4 grams gold per tonne over 1.5 metres, in porphyritic andesites. Three additional holes were drilled south of the anomaly on targets defined by surface mapping and geophysical surveying. No significant results were encountered.
Exploration is currently focused on following up and testing targets identified from previous work.
IMA is endeavouring to raise the Narelle and Panorama targets, also at Potrerillos, to drill status. This involves further grid-based mapping, geochemical sampling and geophysics.
At Rio de la Taguas, ground geophysical surveys have outlined a 600-by-250-metre chargeability anomaly in the area known as Ridge, immediately down-slope of argillic-altered volcanics that contain elevated levels of arsenic and gold.
Barrick has until August to decide if it will continue with an option to earn a 50% interest in either Potrerillos or Rio de las Taguas. To do so, the major must pay must pay IMA US$250,000 and spend a total of US$3 million on exploration over five years. It can earn an additional 25% interest by agreeing to provide financing for IMA’s share of costs to bring the property into production.
Barrick currently holds a 22% equity interest in IMA.
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