LATIN AMERICA — Durango’s Barrancas region a potential new

Only in a few areas of Mexico is gold the major ore in the local economy. One of these areas is in Durango state, between the towns of Pueblo Nuevo and Jocuistle in a geological region known as “Barrancas,” forming part of the Western Sierra Madre mountain range. This area has been lightly explored.

A typical sample of the veins in the area has the following composition: 15 grams gold and 50 grams silver per tonne, 0.5% copper, 0.75% lead and 1% zinc. Few metallurgical tests have been performed on oxide ore samples from the Pueblo Nuevo area. However, results indicate that flotation and cyanide methods would be the best means of recovery.

Many prospectors in the area recover gold through the amalgamation method at washout operations using gasoline motors. The estimated recovery rate is 40-50%. Some reports place the number of washout operations in Pueblo Nuevo and Jocuistle at about 25. Total annual production of 20 kg gold is estimated. Pueblo Nuevo has some interesting and attractive advantages for gold mining. An important one is that there has been no major mining development in the area of study, encouraging the belief that a large volume of ore could exist there. In late 1990, a small company began development of a deposit near Agua Caliente and a Canadian company reported having explored the area around Rio San Diego about 40 years ago.

The lack of organized mining activity is the main reason why the area has not been explored. But it also has to be considered that the area is lacking roads and electrical energy and that gold prices were low prior to 1972. Based on the surveys, maximum reserves of 500,000 tonnes are estimated. That could limit production to 200 tonnes daily.

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Industrial Minera Mexico reports that the production level of zinc at its San Luis Potosi plant stood at about 96,000 tonnes at the end of 1992. Damage caused by a fire from a transformer explosion and a workers’ strike that lasted more than two months interfered with production last year. — Prepared by the Mexican Investment Board, Mexico City.