Corriente drills change gears

Vancouver — Corriente Resources (CTQ-T) has wrapped up its 24,000-metre drill program on the Warintza, Mirador and Panantza properties and plans to focus on evaluating the secondary copper mineralization at Warintza.

Results confirm the discovery of four porphyry copper deposits, including Warintza, Mirador, Panantza and San Carlos (previously drilled by Billiton). Corriente reports that a number of these deposits have a core of high-grade primary mineralization that ranges from 0.7% to 1% copper. These high-grade cores have been the focus of the company’s exploration on the belt to date.

Corriente calculated the weighted averages of drill intersections from the four main prospects. The intersections were in excess of 15 metres and met a cutoff grade of 0.65% copper. The results are as follows:

• The Mirador project an average of 0.79% copper, 0.225 gram gold and 45 ppm molybdenum per tonne, based on intersections from 34 holes;
• The Panantza project an average of 0.83% copper, 0.096 gram gold and 92 ppm molybdenum, based on intersections from 23 holes;
• The San Carlos project an average of 0.85% copper, 0.041 gram gold and 61 ppm molybdenum, based on intersections from 17 holes; and
• Warintza an average of 1.13% copper, 0.098 gram gold and 312 ppm molybdenum, based on intersections from 11 holes.

The average grades at Mirador, Panantza and San Carlos are a reflection of primary sulphide mineralization (chalcopyrite). At Warintza, the mineralization is dominantly secondary copper — chalcocite. Hence the much higher average grade.

Corriente says its next phase of work will focus on an evaluation of higher-grade, secondary copper mineralization discovered on the Warintza prospect. Drilling is scheduled to commence in late June. It will target the high-grade secondary copper blanket discovered last spring during scout drilling. Hole W-01 cut 82 metres grading 1.37% copper and hole W-07 hit 95 metres of 1.2% copper.

Corriente says it will also target outlying copper-molybdenite anomalies in a reconnaissance program.

Located near the Peruvian border, the Corriente region hosts porphyry copper bodies, most of which were discovered by Billiton in the mid-1990s.

Corriente signed two separate (but similar) agreements with Billiton in October 1999 and April 2000.

Under the agreements, Corriente is required to complete a feasibility study on any one of several projects in order to earn a 70% interest in the joint venture. The junior must also issue Billiton up to 2.3 million units (the final number depends on which prospects are included). Each unit consists of a share and a share purchase warrant.

Upon completion of the feasibility study, Billiton will have three options: maintain its 30% interest; retain a 70% back-in right by providing production financing; or dilute to a 15% net profit interest.

David Lowell, who is associated with the Pierina gold discovery in Peru and the Escondida project in Chile, is running the exploration program. He holds 10% of Corriente’s interest through his own Chilean-based company, Lowell Mineral Exploration.