Nevsun ends Bisha drilling on high note (August 11, 2004)

Vancouver — Infill drilling by Nevsun Resources (NSU-T) at its Bisha project in Eritrea, East Africa, has outlined high grades in all three levels.

Nevsun has tightened the drill spacing to 25 metres at the main zone to confirm the extent of the gold-bearing oxide and supergene copper zones over 1,200 metres of strike length. Drilling also tested the deeper primary sulphides zones containing copper and high-grade zinc, which are still largely open.

Results throughout the program outlined significant mineralized intercepts in all three zones. The primary zone remains open to the south, north and at depth.

More than 31,250 metres were drilled in 195 holes. The latest results are for holes 300-309 and nine reverse-circulation/diamond drill holes. Fifteen water wells were also drilled. The data will be used to estimate the resource for each zone, and will form the basis of a feasibility study for the project.

Recent drill highlights include the following:

Oxide zone

• Hole B-303 — 7.16 grams gold over 43.4 metres.
• Hole BRCD-037 — 8.53 grams gold over 16.7 metres.
• Hole BRC-039 — 28.23 grams gold over 19.5 metres.
• Hole BRCD-041 — 8.73 grams gold over 15.8 metres.

Supergene zone

• Hole B-304 — 12.94% copper over 7.5 metres.
• Hole B-308 — 4.04% copper over 34.5 metres.
• Hole B-309 — 5.17% copper over 15.1 metres.
• Hole BRCD-034 — 4.72% copper over 30.3 metres.

Primary zone

• Hole B-301 — 8.67% zinc and 1.95% copper over 38.5 metres.
• Hole B-304 — 8.66% zinc and 1.7% copper over 27.6 metres.
• Hole B-305 — 12.17% zinc and 1.07% copper over 28.1 metres.

BRC holes were drilled by reverse circulation methods, BRCD holes started out with reverse-circulation and finished with diamond drilling to enable deeper drilling. (Zinc-enriched sections were cut to 2%.)

The Bisha Main zone represents a volcanogenic massive sulphide deposit in which three areas of mineralization have been outlined: the high-grade gold oxide zones extend from the surface to approximately 35 metres depth; directly below the oxide zone are the copper supergene zones, 30 metres wide, which extend to a depth of about 65 metres; and there is copper immediately below the supergene zones, with wide, high-grade zinc intercepts within primary massive sulphides.

The primary sulphides were tested along the 1.2-km strike length to varying depths of up to 375 metres in the southern portion of the Bisha Main deposit. A block model based on the drilling done so far will be verified by the engineering company AMEC, which will be estimating the resource for release in September.

Baseline studies for environmental studies are under way. The next round of drilling, slated for October, will test a new geologic model to determine the overall size and extent of the deposit. Whole rock geochemistry provided some clues for the geologic interpretation and a better understanding of the emplacement and subsequent structural deformation of the massive sulphide mineralization. The resource model will be based on the new geologic model. The property is largely underlain by mafic and felsic volcanic rocks with a large gabbro body in the southeastern corner.