With an area of approximately one hundred square kilometres and situated between the municipalities of Marbella, Ojén and Mijas, the peridotite massif of the Sierra de la Alpujata is the second largest ultramafic outcrop in the province of Málaga.
It is mainly composed of peridotites from the upper mantle that ascended to the earth's crust as a result of the lithospheric shearing of the alpine folding that occurred during the Oligocene period (approximately 23 million years ago), undergoing metamorphic processes by which they became Magnetites and Serpentinites, mainly in their variety of Iherzolites.
The deposits of the Sierra de la Alpujata have been exploited throughout history for the great variety of minerals they contain. There are mines such as La Gallega, La Concepción or Peñoncillo or Los Linarejos, all of which have been abandoned to this day, where iron, talc, nickel, chrome, lead, cobalt and many other species have been extracted.
Singularly important was the Concepción iron mine, which began to be exploited in 1826 by "La Concepción Iron Mining & Steel Corporation", a company created by a famous businessman from Malaga named Manuel Agustín Heredia, who installed a foundry in which practically 75% of the iron extracted in Spain in the 19th century was produced and gave an important boost to the economic life of the area. The mine later passed into the hands of the English company "The Marbella Iron Ore Company Ltd", which kept it active until the last quarter of the 20th century, even installing a funicular railway by which they transported the iron to the sea, to be shipped to the United Kingdom.
