Pozo Rico Silver Mine, Guadalcanal, Sierra Norte
In 1555 a Silver mine called Pozo Rico outside Guadalcanal was rediscovered. It soon became one of the most important Silver mines in Spain, perhaps Europe and it was probably named after the world's biggest, the Cerro Rico mine of Potosi, Bolivia.
The silver is found bound in minerals in veins or seams of hydrothermal vents, which also include lead, zinc, copper. In Iberian geological terms Guadalcanal is found in the Ossa-Morena zone and the rock is of the lower Cambrico period (about 500m years ago).
At the Guadalcanal countless royal concession holders made and lost fortunes. They were hampered by lack of technology, lack of capital, lack of infrastructure in this remote backwater of the Sierra Norte de Sevilla on the Andalucia - Extremadura border.
Notable concession holders in the late sixteenth century included the Fugger family (German Augsburg banking family) who pulled out leaving behind rumours that they had hidden large sums of gold behind a false wall in the mine down at level 10.
In 1729 the Compañia Española headed by Conde de Cogorani contracted Lady Mary Herbert de Powis to drain the Guadalcanal mine. This was completed in 1732 after not being paid for the work Lady Mary won a ten-year litigation and in 1742 was awarded Guadalcanal concession directly along with that of Rio Tinto mines.
The Guadalcanal mine was last worked in 1914 although there have been several investigation licences granted since.
Pozo Rico in Guadalcanal has never been worked as an opencast mine, thus the natural landscape is preserved.
Today one can view and enter, a little way, into a number of horizontal mine audits where the mines were worked by hand and the galleries followed the seams and were only widened in bonus areas.
The 90ft Pozo Rico shaft opening is protected and a modern pump extracts water to irrigate the adjacent olive groves.
The 150ft San Antonio shaft next to the old building was backfilled some years ago to prevent animals falling and subsidence.
Location
Today the mine is located on a private estate, and the landowner's permission must be sought from Emilio at Finca Molionero before exploring.
Leave the A-433 at km 14 signposted "Sanctuario de Nustra Sñra de Guaditoca" and immediately taking the unmade track on the right hand side for 4km. Take a right fork towards Finca Molinero. The mine is located at GPS 38.100762 N and 5.780613 W.
References
"Algunso datos Historicos Sobre La Mina de Plata de Pozo Rico" . A paper by Octavio Puche Riart, ESTI Minas y Energia. Madrid Published in 'De Re Metalica' 25, 2015 pp27-32 Sociedad Española para la defensa del Patrimonio Geologico y Minero.