According to Extrareference, the Spanish subsoil offers a conspicuous range of mineral resources, many of which have been known and exploited since ancient times. Of particular note are iron ores, mainly extracted from Cantabrian deposits, therefore from those of the Iberian and Betic systems; among the other metal ores, a place of primary importance goes to lead, coming from the Sierra Morena, and zinc, extracted in the region of Santander and in the Basque Provinces, for both of which Spain occupies an excellent place at European level. Well known is the mercury of Almadén (Ciudad Real), already known in Roman times and for whose production Spain ranks among the first world producers, also exploiting the fields of Mieres and Pola de Lena. The copper deposits are of lesser importance. The country, on the other hand, stands out for its pyrites, prized for their high sulfur content, with main deposits in the Ríotinto area. The annual production of rock salt and brine is also conspicuous; still signal the potash, the magnesite, then manganese, antimony, tungsten, tin, bauxite, gold and silver. The coal reserves, whose main basin is the Asturian-Leonese one, are discrete, but are nevertheless totally insufficient for the needs of the industry; oil production is of little importance (fields near Valladolid, Burgos and off the coast of Tarragona), to which are added rather modest quantities of uranium extracted in the Lérida area, and natural gas. As for the energy sector, although it has been strengthened, the production of electricity remains considerably lower than that of the industrialized countries of Western Europe. At first, electricity was essentially of water origin, thanks to the construction of numerous power plants located initially on the upper course of the rivers, especially in the region of the Eastern Pyrenees, as a function of the industries of Catalonia, then along the middle course of the major river arteries (Ebro, Duero, Tagus), thus favoring various other cities, such as Valladolid and Madrid.
However, thermal energy has taken on an increasingly important role thanks to the numerous thermal power stations, mainly located in the North, the Levant and Andalusia, fueled both by domestic coal and, increasingly, by imported oil. Over a third of energy production is provided by the nuclear sector, thanks to the Zorita (Guadalajara), Santa María de Garoña (Burgos) and Vandellós (Tarragona) power stations, which exploit uranium extracted in Lérida. Thanks to the inflow of foreign capital that followed the entry into the EEC (1986), the Spanish industry has considerably modernized and diversified from the production point of view. It constitutes a supporting structure of the national economy: in addition to the consolidation of production capacities, it has undergone significant progress in the qualitative composition. The main industrial districts continue to be those with the oldest plant, namely the North of the country (essentially the Basque Provinces), where numerous mechanical complexes operate, benefiting from the mineral resources of the Cantabrian area, Catalonia, which, in addition to the traditional textile activities, now has very active chemical and mechanical industries and steel processing, the Levant, where the food sector is always very flourishing (Valencia); finally the area around the capital, which includes important chemical and mechanical complexes. The Spanish industry of the beginning of the century. XXI covers almost all productive sectors, even if it shows a continuous increase of the manufacturing industry compared to the extractive one, which was at the origin of fundamental importance in the country’s economy. Good European standard presents the steel industry, concentrated in the Vizcaya area (Basque Provinces), in Asturias, in Catalonia (production of special steels) and in Sagunto (Valencia). The main products of the metallurgical industry, which has a more varied and articulated location and which to a large extent also processes imported minerals, now reaching respectable productions on a European scale, are aluminum (in Valladolid, Avilés, Lagrela and Sabáñago), copper (Ríotinto, Cordoba, Barcelona, Palencia, Bilbao), lead, tin, zinc; moreover, a large part of the coal extracted is transformed into coke metallurgical. Uranium ore is refined at the Andujar plant. The mechanical sector has had a significant development, aimed primarily at the construction of means of transport, but also of machinery of all kinds and various tools. Thus locomotives and railway equipment are produced in Barcelona, Madrid, Valencia; the Asturian-Basque steel district supplies steel rolled products, rails, etc.; high precision machinery is also produced in Barcelona.
The automotive industry, in which the participation of foreign companies has had and continues to have a decisive role, is mainly located in large cities. The thriving rubber industry is largely linked to it, headquartered in Barcelona. The naval industry has its main centers in El Ferrol, Cartagena, Cádiz, Barcelona and Bilbao; Seville and Cadiz are also home to aeronautical complexes. The chemical industry has experienced extraordinary expansion; it is concentrated in Catalonia, but various plants have also sprung up in the Asturian-Basque area, favored by the by-products of metallurgy, as well as in certain inland centers, such as Madrid, Valladolid and Zaragoza. Excellent is the production of sulfuric acid, which is obtained from the abundant national pyrites; a minor but not modest role in the European context is also played by the production of nitrogen fertilizers, synthetic resins and plastic materials, nitric acidand hydrochloric, caustic soda etc. The textile industry retains its role, in particular the cotton industry, widespread mainly in Catalonia. The wool mill has a minor importance, to which are added good productions of artificial and synthetic textile fibers, linen yarns, hemp, jute etc. The pre-eminent food industry is the sugar industry, which operates for the most part in the production areas of sugar cane and sugar beet, with main factories in Zaragoza and in other centers of the Ebro valley; of importance are also the beer industry, oil mills, canning plants, dairy ones; the tobacco factories. The paper industry has its greatest location in the Basque Provinces, Catalonia and Valencia. Glass processing (which boasts numerous factories, including notable ones in Bilbao and Arija, near Santander, in La Granja, etc.), in ceramics (in Talavera de la Reina, in La Cartuja near Seville, in Manises and Segovia), tanning of hides and leather complete the picture of the Spanish industry. Particular dynamism shows the sectors of electronics and telecommunications.