Pudahuel and Potrerillos
Geographically speaking, there lie between El Teniente and Chuquicamata two other large copper deposits acquired by North American interests since the European War. Between Santiago and the sea lie the Pudahuel mines, identified at least a hundred years ago, worked for their rich surface veins, and now owned by the Andes Copper Company, a subsidiary of the Anaconda interests. Immense masses of low-grade ores, rivalling those of the Guggenheim interests in extent, are said to be available, but although in 1920 projects for a big plant were under active development, work was slackened by depressed markets and the operation of the deposits is not yet in sight.
A similar fate has befallen the widely heralded plans connected with another Anaconda property, a huge deposit of low-grade copper ores at Potrerillos, in the Andean spurs east of the railway junction at Pueblo Hundido in Atacama province. The main ore bodies lie in a ravine about 12,000 feet above sea level and consist chiefly of sulphides and oxides. At the time when I visited the region in late 1920 the treatment of these ores had not been decided upon, and no machinery installed, although an expensive housing scheme had been carried out at the mine. A railway between the tiny village of Pueblo Hundido, a handful of houses in the middle of an apricot-hued desert, and the high-placed mine were in operation; and a power plant, burning petroleum, had been set up at Barquito, on the coast a few miles south of Chañaral, the transmission lines running out across the sandy waste for some 130 miles.
Work on the Potrerillos installation was suspended about the middle of 1921, before a single ounce of copper had been produced. High above the copper deposits are extensive beds of sulphur, and upon the extraction of this mineral, needed in certain processes employed in treating low-grade ores, a certain amount of work has been done.
There are 16,000 mines of copper registered in Chile, covering an area of 57,000 hectares upon which the mining tax of ten pesos per hectare is paid. Of the producing establishments, Chuquicamata and El Teniente are by far the greatest, exporting in 1918 nearly eighty per cent of Chile’s total production. From the Caldera smelters was shipped a total of 5217 metric tons; Catemu produced 3790 tons; Gatico, 3708 tons; Naltagua, a French property, 3653 tons. Small quantities came also from El Volcán, El Hueso, and the Chañaral smelters, also in French hands. For the last ten years Chile’s output of copper in comparison with the total world supply has varied between 4 per cent in 1911 and 1912, and 8 per cent in 1918. By far the greatest producer of copper today is the United States, with a highest record of 880,000 metric tons in 1916, followed by Japan, shipping her highest recorded figure in 1917, when 124,000 tons was produced; Mexico, 75,000 tons; Canada, averaging 50,000 tons; and Peru, 45,000.
Iron
The story of Chile’s iron deposits and works offers one of the most curious chapters in her mining history.
The most important of the identified deposits lie in the desert country north of Coquimbo, the fields at El Algarrobo and Algarrobito in the Department of Vallenar, Atacama Province, having interested a German firm some years before the war. No practical results were achieved, although the region recorded a small export of manganese, from the Astillas beds, until economic conditions checked these shipments soon after the beginning of this century. Proximity of quantities of manganese ore to the iron fields, reported as being of immense extent, has raised repeated hopes for the foundation of a great industry, but the crux of the problem is the absence of adequate fuel or water supplies, and the unproductivity of a sterile territory.
The only works so far established in connection with Chilean iron ores depend upon what is the most remarkable ferruginous deposit on the West Coast, paralleled only by the Itabira peaks in Brazil and the iron mountain of Durango in Mexico. El Tofo, some forty miles north of Coquimbo town, and fifteen miles from the Pacific, is a round hill practically composed of hematite ores running over 65 per cent pure, the quantity in sight totalling at least 300,000,000 tons. The hill stands among an imposing array of rolling mountains, and both dwellings and mine workings are daily enshrouded in seas of white mist.
Early in the present century this huge deposit was acquired by a French company, the Société Altos Hornos de Corral, which mined a quantity of the ores and transported them by light railway to the little bay of Cruz Grande and thence to the south where, at the port of Corral in Valdivia province, a smelter was erected, the first experimental production of pig-iron taking place in 1910.