Western Copper advances projects

The latest results from a series of eight infill holes continue to confirm the continuity and grade of the San Nicolas polymetallic deposit in the central Mexican state of Zacatecas.

The holes were completed on 50-metre centres, primarily for geotechnical and geostatistical purposes. Drilling is continuing to delineate the limits of the main sulphide zone, as well as a lower copper zone, on 100-metre stepouts.

San Nicolas is part of the El Salvador project, a 55-45 joint venture between Teck (TEK-T) and Western Copper Holdings (WTC-T). The massive sulphide deposit occurs in the western portion of the project area, on ground optioned from Luismin, a Mexican mining company. Luismin is carried through completion of a feasibility study, at which point it may either participate at 25% by arranging its share of production financing or dilute to a 15% interest.

Teck recently announced that the deposit is estimated to contain a reserve amenable to open-pit mining of 72 million tonnes grading 2.27% zinc, 1.35% copper, 0.53 gram gold and 30 grams silver per tonne, at a stripping ratio of 7.8 to 1. The preliminary reserve calculation was based on results from the first 34 drill holes. A total of 50 holes had been completed at last report.

The deposit lies beneath 160 metres of volcanics and conglomerates, such that development would require pre-stripping of 100 million tonnes of waste.

The reserve estimate includes a higher-grade zinc zone comprising 19 million tonnes grading 6.15% zinc, 0.79% copper, 1.32 grams gold and 73 grams silver that sits atop the main deposit.

Immediately north of the El Salvador project area, Western Copper holds an option on the 141,600-ha Villa de Ramos project, part of its strategic alliance with Rio Tinto (RTP-N) subsidiary Kennecott. The alliance covers 485,600 ha of promising projects in the states of Zacatecas and San Luis Potosi.

Western Copper is committed to spending US$1 million per year on exploration over a 5-year period. However, once the Vancouver-based junior has incurred the first year’s expenditures, Kennecott will transfer a 100% interest in the concessions to the junior. Kennecott retains a 2% net smelter return royalty of up to US$15 million on any of the concessions, which can be converted to a 51% back-in right on any concession in the alliance area, including the Penasquito project.

Western Copper is currently advancing a number of these projects. At Villa de Ramos, the company reports that gravity surveying has defined at least five discrete anomalies in areas of favorable geology. Two of the gravity anomalies coincide with reconnaissance induced-polarization (IP) anomalies.

Real-section, dipole-to-dipole IP surveys will be completed over the five gravity anomalies in preparation for drilling scheduled to begin in July.

Following completion of the Villa de Ramos drilling, a coincident gravity, IP and copper anomaly on the San Jeronimo project will be drilled.

Geological mapping on the 182,100-ha San Pedro property, 225 km southeast of El Salvador, has identified copper showings and favorable felsic rocks. A reconnaissance IP survey is scheduled to begin in late July, to be followed by gravity surveys.

In addition, Western Copper began a 3,000-metre diamond drilling program on the 100%-held Penasquito project in April. The program was designed to test partially defined mineralized zones and geophysical anomalies previously identified by Kennecott.

Penasquito covers 3,255 ha in the Concepcion del Oro district, 200 km northeast of the city of Zacatecas. Since 1994, Kennecott has carried out geochemical and geophysical surveys and has completed 71 holes totalling 23,495 metres. This work identified the Chile Colorado polymetallic zone, as well as two large breccia pipes and several outlying targets that returned high-grade intercepts.

Five previous holes in the Chile Colorado zone intersected polymetallic mineralization within an area 400 metres in length, 250 metres in width and 150 metres in depth, starting at a depth of 170 metres. Western Copper completed four holes in the zone. Hole WC-1 was collared 100 metres west of Kennecott hole PN-28, which had intersected 7 metres (from 204 metres downhole) grading 4.89% zinc, 5.24% lead, 0.22 gram gold and 357 grams silver, plus 150 metres (from 226 metres) averaging 1.45% zinc, 0.18% lead, 1.05 grams gold and 72 grams silver. WC-1 intersected narrow intervals of high-grade mineralization averaging 0.79% zinc, 0.28% lead and 53 grams silver over a core length of 219.7 metres, starting at a depth of 198.8 metres.

Hole WC-3 encountered 99.2 metres (from 153.1 metres) averaging 2.48% zinc, 2.15% lead and 189 grams silver, including a 17.1-metre intercept averaging 5.2% zinc, 4.76% lead, 0.58 gram gold and 406 grams silver. The hole was collared 165 metres east of Kennecott hole PN-26 and drilled due west, perpendicular to the orientation of the other holes.

Hole WC-5, collared 100 metres north of hole 3, intercepted 134.6 metres (from 240.6 metres) averaging 2.08% zinc, 0.03% lead, 0.65 gram gold and 15 grams silver. Hole WC-8, collared 50 metres south of hole 3, hit 45.6 metres (from 164 metres) averaging 1.41% zinc, 1.06% lead, 0.13 gram gold and 68 grams silver.