Linares – La Carolina was one of the twelve mining districts existing in Spain in 1841 and Linares was its head, hosting the official mines inspection.
The district consists of eight municipalities and is divided in two parts with different geological and morphological characteristics. The southeaster area includes vicinities of Bailén, Linares, Vilches and Guarromán, with a countryside landscape and the Sierra Morena foothills. The surface of the country here is a successive undulation of hills and valleys. These valleys are clearly product of erosion process. Granite is the dominating rock here and the metalliferous veins cut it with regular and clean fissures according almost vertical plans and mainly following a southwester to northeaster direction.
The northwester area of the district includes vicinities of Baños de la Encina, Carboneros, La Carolina and Santa Elena with the mountainous landscape of Sierra Morena. In it, there is an argillaceous slate overlying the granite. Here the metal-bearing veins also transverse both the granite and the slates. The original lodes field origin is the same that in Linares area, with veins in four different directions.
Along the 19th century many mining companies, Spanish as well as British, French, German or Belgian, asked the mining national authorities for permission to work the rich veins of galena. Each permission, called concession, consist in a square or rectangular surface with unlimited depth, that the company could work for 30 years that could be renewed.
There are extensive mining concessions in both the Linares and La Carolina mining as shown on the two plants. Their relationship is shown on the third plan.
In 1888, 36 mining companies were installed in Linares, 26 Spanish and 12 foreigner. The district had 536 mining concessions, but only 213 were fruitful. 118 of them were located in Linares and 95 in the other municipalities of the district (Revista Minera number 39, pages 141 – 142). In moments of highest activity there were more than one thousand concessions.
Each concession had to be registered by the district mining engineers, and demarcated by stone landmarks located in the corners to identify the ownership.