Rio Narcea expands mineralization in Spain

Rio Narcea Gold Mines (RNG-T) has announced promising results from drilling programs in Spain.

Stepout drilling at the gold-silver-copper project known as El Valle is delineating a major extension to the currently defined gold and copper mineralization below the Boinas East open pit. Hole Boi 110, testing the Black Skarn zone, 75 metres to the east of the nearest updip hole, encountered a true thickness of 17.7 metres averaging 5.5 grams gold per tonne, 32 grams silver and 2.5% copper at a depth of 209.3 metres. The intercept is within a zone of mineralization with a true thickness of 99.7 metres averaging 2.5 grams gold, 17.9 grams silver and 1.1% copper.

Rio Narcea President Alberto Lavandeira says the hole “demonstrates a potential for reserve growth at El Valle that few of us could have imagined a year ago.”

The infill program to the west continues to define an area of strong gold mineralization below the Boinas East pit. Recently completed hole Boi 103 intercepted an upper zone with a true thickness of 53.3 metres averaging 8.5 grams gold, 47.3 grams silver and 0.5% copper at a depth of 163 metres; a middle zone that averages 3.2 grams gold, 42.8 grams silver and 0.8% copper over a true thickness of 23.5 metres at a depth of 271 metres; and a lower zone with a true thickness of 24.8 metres averaging 5.6 grams gold, 18.3 grams silver and 0.4% copper at a depth of 308 metres.

These intercepts are included within a large envelope of mineralization with a true thickness of 186 metres averaging 4.3 grams gold, 28.2 grams silver and 0.4% copper.

The southeast-dipping zone of gold-copper skarn is enriched by an epithermal feeder structure over a width of 20 to 40 metres at depth and which widens upward to 160 metres in the upper Black Skarn zone. The company has been closing the drill-hole spacing on the structure to 25 metres. The strongly oxidized and silicified zone within the skarn has a proven strike length of 75 metres and an indicated strike length of 200 metres.

Hole Boi 100, another infill hole drilled to test the feeder zone 25 metres northeast of hole Boi 103, encountered 5.6 grams gold over a true thickness of 30.2 metres at a depth of 119 metres. At a depth of 165.2 metres, Boi 100 intercepted 13.1 metres averaging 7.4 grams gold, and at 249.5 metres it intercepted a true thickness of 42.3 metres averaging 3.8 grams gold, 43.4 grams silver and 0.6% copper. Hole Boi 98, drilled 25 metres northeast of hole Boi 100, encountered a similar section of gold and copper mineralization with a true thickness of 60.2 metres averaging 3 grams gold, 21.2 grams silver and 0.4% copper.

The company now has nine drill rigs operating on its properties in northern Spain. Four rigs are dedicated to the exploration and delineation of new zones of gold mineralization at El Valle; three rigs are completing infill drilling on the Carles property, 9 km north of El Valle; and two rigs are testing exploration targets at Godan and in the northern Oscos gold belt.

Rio Narcea recently exercised an option to buy the Metamorphica, Aurita and Plinio mining concessions from Minera de Salas for US$532,138. Covering a total area of 15.3 sq. km in the northern Rio Narcea gold belt, the concessions include the Godan prospect, where ongoing exploration drilling has discovered gold mineralization associated with the Ortosa granodiorite intrusive.

The Godan prospect contains both skarn and epithermal gold mineralization near a large intrusive body in the same stratigraphic section that hosts the copper-gold skarn mineralization at Carles.

Discovery hole Ort-11 identified two zones of gold mineralization along the western contact of the intrusive. The upper zone includes 1.8 metres averaging 20.6 grams gold in a highly fractured garnet skarn at a depth of 77 metres. The lower zone consists of strongly altered granite with endoskarn that averages 7.2 grams gold over a true thickness of 11 metres at a depth of 237 metres. Nearby hole Ort-14 intercepted a similar section in the lower zone.

Drilling is focusing on the edge of a strong magnetic anomaly immediately to the south of the intrusive.

.SOrtosa intrusive

An analysis of a large zone of alteration in unassayed core from early drilling on the Ortosa intrusive defined porphyry copper geochemical zonation, including large and continuous intercepts of low-grade gold mineralization. Hole Ort-8, drilled vertically into the heart of the altered zone, encountered anomalous gold from the surface, with 221 metres averaging 0.1 gram gold and 76 metres averaging 0.02% copper.

The Godan results follow encouraging values from the company’s earlier exploration program, 750 metres to the east, which targeted mineralization below the Godan Roman pit. Here, hole Sal-5 intercepted 13.7 metres of silicified carbonate with arsenopyrite, averaging 1.9 grams gold at a depth of 145 metres. At 70 metres downdip, hole Sal-6 intercepted 1.9 metres of 2.12 grams gold at a depth of 253 metres and 3.19 grams gold and 1.2% molybdenum over a drilled thickness of 2.5 metres at a depth of 276 metres.

.SGold, copper values

The intrusive contains strong potassic and propylitic alteration which is similar to a porphyry style of mineralization, though it but may represent more than a single mineralizing event, say Rio Narcea officials.

Meanwhile, Rio Narcea has entered into a contract with Fluor Daniel for construction of the milling and gold processing plant at El Valle. The contract is a lump-sum, turn-key agreement, and much of the work will be conducted by Fluor Daniel’s wholly owned subsidiary, Signet Engineering of Australia.

The plant is designed to recover more than 100,000 oz. gold per year using a 3-stage process comprising gravity, flotation and cyanidation. Full-scale production is scheduled to begin in the first quarter of 1998.

“The skills of Fluor Daniel, one the world’s leading design, engineering and construction firms, along with the very significant gold expertise of Signet, give us confidence that El Valle will be brought into production on schedule and within budget,” says Lavandeira.