Teck to drill Argentine prospects

A first round of drilling on the Rio Grande joint-venture property in northwestern Argentina is to begin early in the new year.

Teck (TEK-T), the operator, can earn an initial 55% interest in the property from Mansfield Minerals (MDR-V) by spending $4 million on exploration over four years and paying $1 million.

The property is in the Puna region, 250 km due west of Salta.

In a 1999 regional program jointly funded by Teck, Mansfield discovered a zone of disseminated and veinlet-controlled chalcopyrite and magnetite mineralization hosted by intense, potassically altered volcanic rocks.

The discovery area has a surface footprint measuring 700 by 200 metres and lies within a larger, zoned, hydrothermal alteration system that appears to be 2 km long and 1.9 km wide. Mansfield says the Rio Grande prospect displays the typical mineralogy, metal suite and alteration styles characteristic of an Olympic Dam-style iron oxide-copper-gold prospect.

In March, Teck exercised its right of first refusal and optioned the property. The major initially excavated three hand trenches on the discovery showing, which were channel- or chip-sampled at 1-metre intervals. Two cross-trenches were completed in a northerly and easterly direction. The easterly striking trench averaged 0.58% copper and 0.98 gram gold over 96 metres, while the north-south leg averaged 0.72% copper and 1.1 grams gold over 30 metres.

A further 450 metres to the southwest, the third trench averaged 0.31% copper and 0.22 gram gold over a 19-metre section.

Teck recently completed a 2,000-metre program of mechanized trenching, comprising some 17 trenches, over targets generated through geochemical sampling and magnetometer surveys. The trenches are currently being sampled.

In recent weeks, Mansfield has climbed to the 70 range from 55, with a notable increase in trading volume. Douglas Leishman of Yorkton Securities reports that Mansfield had received photographs of some of the areas being trenched, and in at least one instance, it appears copper oxide mineralization has been identified over a relatively large area. There are indications that some areas might be associated with breccia pipes, implying a vertical component.

In addition, Mansfield holds a 100% interest in the Arizaro property, 12 km southeast of Rio Grande, where it has identified two similar styles of targets. The junior has launched a 2,500-metre program of excavator trenching to test a 900-by-1,200-metre copper-gold geochemical anomaly as defined by a recent soil and talus sampling program. Two previous hand trenches, dug in a potassically altered area, yielded 22 metres of 0.59% copper and 1.18 grams gold, plus 8 metres of 0.66% copper and 1.44 grams gold.

A second zone of copper-gold mineralization, dubbed Lindero, will also be trenched, with 1,000 metres planned.

Elsewhere in the region, Teck has committed to a limited 3-to-4-hole drill program of up to 1,000 metres on the Cerro Samenta property, 25 km northwest of Rio Grande. Teck will test the newly discovered El Camino zone, where local specular hematite, fluorite and copper-gold-zinc mineralization occur in more than a dozen zones in a 1-by-4-km area on the southeastern portion of the property.

Mineralization in the El Camino zone is separate and distinct from the previously tested porphyry copper-molybdenum mineralization and may represent the upper levels of a Rio Grande or Arizaro type system.