Las Médulas
Encyclopedia
Las Médulas is a historical site near the town of Ponferrada
in the region of El Bierzo
(province of León
, Castile and León
, Spain
), which used to be the most important gold
mine
in the Roman Empire
. Las Médulas Cultural Landscape is listed by the UNESCO
as one of the World Heritage Site
s.
The spectacular landscape of Las Médulas resulted from the Ruina Montium, a Roman mining technique described by Pliny the Elder
in 77 AD. The technique employed was a type of hydraulic mining
which involved undermining a mountain with large quantities of water. The water was supplied by interbasin transfer
. At least seven long aqueduct
s tapped the streams of the La Cabrera
district (where the rainfall in the mountains is relatively high) at a range of altitudes. The same aqueducts were used to wash the extensive gold deposits.
The area Hispania Tarraconensis
had been invaded in 25 BC by the emperor Augustus
. Prior to the Roman conquest the indigenous inhabitants obtained gold from alluvial deposits. Large-scale production did not begin until the second half of the 1st century AD.
The description could well have applied to Las Medulas. Since Pliny was a Procurator
in the region in 74 AD, it is highly likely that he saw mining operations for himself, and his text reads like an eye-witness report. He also describes the methods used to wash the ores using smaller streams on riffle tables to enable the heavy gold particles to be collected. Detailed discussion of the methods of underground mining follows, once the alluvial placer deposit
s had been exhausted and the mother lode sought and discovered. Many such deep mines have been found in the mountains around Las Medulas. Mining would start with the building of aqueducts and tanks above the mineral veins, and a method called hushing
used to expose the veins under the overburden.
The remains of such a system have been well studied at Dolaucothi in South Wales
. Opencast methods would be pursued by fire-setting
, which involved building fires against the rock and quenching with water. The weakened rock could then be attacked mechanically and the debris swept away by waves of water. Only when all opencast work was uneconomical would the vein be pursued by tunnelling and stoping
.
Pliny also stated that 20,000 Roman pounds of gold were extracted each year. The exploitation, involving 60,000 free workers, brought 5,000,000 Roman pounds (1,650,000 kg) in 250 years.
Research on Las Médulas had been mainly carried out by Claude Domergue (1990) . Systematic archaeological studies of the area, however, have been carried out since 1988 by the research group Social Structure and Territory-Landscape Archaeology of the Spanish Council for Scientific Research (CSIC
). As a result, Las Médulas ceased to be only a gold mine with its techniques and became a cultural landscape
in which all the implications of Roman mining were made apparent. The survey and excavations of pre-Roman and Roman settlements throughout the area allowed for new historical interpretations that greatly enriched the study of Roman mining..
A positive result of these systematic studies was the inclusion of Las Médulas as a World Heritage Site
in 1997. Since then, the management of the Cultural Park has been monitored by the Las Médulas Foundation, which includes local, regional, and national stakeholders, both public and private. Currently, Las Médulas serves as an example of good research-management-society applied to heritage
Ponferrada
Ponferrada is a city in the province of León, Castile and León, Spain. It lies on the Sil River, a tributary of the river Miño, in the El Bierzo valley, completely surrounded by mountains. It is the last major town along the French route of the Way of St. James before it reaches its destination...
in the region of El Bierzo
El Bierzo
El Bierzo is a shire in the province of León, Spain. The valley has the administrative status of comarca and its capital is the town of Ponferrada. Other major towns are Bembibre and Villafranca del Bierzo, the historical capital.- History :...
(province of León
León (province)
León is a province of northwestern Spain, in the northwestern part of the autonomous community of Castile and León.About one quarter of its population of 500,200 lives in the capital, León. The weather is cold and dry during the winter....
, Castile and León
Castile and León
Castile and León is an autonomous community in north-western Spain. It was so constituted in 1983 and it comprises the historical regions of León and Old Castile...
, Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
), which used to be the most important gold
Gold
Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...
mine
Gold mining
Gold mining is the removal of gold from the ground. There are several techniques and processes by which gold may be extracted from the earth.-History:...
in the Roman Empire
Roman Empire
The Roman Empire was the post-Republican period of the ancient Roman civilization, characterised by an autocratic form of government and large territorial holdings in Europe and around the Mediterranean....
. Las Médulas Cultural Landscape is listed by the UNESCO
UNESCO
The United Nations Educational, Scientific and Cultural Organization is a specialized agency of the United Nations...
as one of the World Heritage Site
World Heritage Site
A UNESCO World Heritage Site is a place that is listed by the UNESCO as of special cultural or physical significance...
s.
The spectacular landscape of Las Médulas resulted from the Ruina Montium, a Roman mining technique described by Pliny the Elder
Pliny the Elder
Gaius Plinius Secundus , better known as Pliny the Elder, was a Roman author, naturalist, and natural philosopher, as well as naval and army commander of the early Roman Empire, and personal friend of the emperor Vespasian...
in 77 AD. The technique employed was a type of hydraulic mining
Hydraulic mining
Hydraulic mining, or hydraulicking, is a form of mining that uses high-pressure jets of water to dislodge rock material or move sediment. In the placer mining of gold or tin, the resulting water-sediment slurry is directed through sluice boxes to remove the gold.-Precursor - ground...
which involved undermining a mountain with large quantities of water. The water was supplied by interbasin transfer
Interbasin transfer
Interbasin transfer or transbasin diversion are terms used to describe man-made conveyance schemes which move water from one river basin where it is available, to another basin where water is less available or could be utilized better for human development...
. At least seven long aqueduct
Aqueduct
An aqueduct is a water supply or navigable channel constructed to convey water. In modern engineering, the term is used for any system of pipes, ditches, canals, tunnels, and other structures used for this purpose....
s tapped the streams of the La Cabrera
Cabreira
La Cabrera is a comarca in the province of León, Spain. Its surface is 115.87 km² and the population was 4,227 inhabitants in 2007...
district (where the rainfall in the mountains is relatively high) at a range of altitudes. The same aqueducts were used to wash the extensive gold deposits.
The area Hispania Tarraconensis
Hispania Tarraconensis
Hispania Tarraconensis was one of three Roman provinces in Hispania. It encompassed much of the Mediterranean coast of Spain along with the central plateau. Southern Spain, the region now called Andalusia, was the province of Hispania Baetica...
had been invaded in 25 BC by the emperor Augustus
Augustus
Augustus ;23 September 63 BC – 19 August AD 14) is considered the first emperor of the Roman Empire, which he ruled alone from 27 BC until his death in 14 AD.The dates of his rule are contemporary dates; Augustus lived under two calendars, the Roman Republican until 45 BC, and the Julian...
. Prior to the Roman conquest the indigenous inhabitants obtained gold from alluvial deposits. Large-scale production did not begin until the second half of the 1st century AD.
Description in Pliny the Elder's Natural History
- "What happens is far beyond the work of giants. The mountains are bored with corridors and galleries made by lamplight with a duration that is used to measure the shifts. For months, the miners cannot see the sunlight and many of them die inside the tunnels. This type of mine has been given the name of Ruina Montium. The cracks made in the entrails of the stone are so dangerous that it would be easier to find purpurine or pearls at the bottom of the sea than make scars in the rock. How dangerous we have made the Earth!"
The description could well have applied to Las Medulas. Since Pliny was a Procurator
Procurator (Roman)
A procurator was the title of various officials of the Roman Empire, posts mostly filled by equites . A procurator Augusti was the governor of the smaller imperial provinces...
in the region in 74 AD, it is highly likely that he saw mining operations for himself, and his text reads like an eye-witness report. He also describes the methods used to wash the ores using smaller streams on riffle tables to enable the heavy gold particles to be collected. Detailed discussion of the methods of underground mining follows, once the alluvial placer deposit
Placer deposit
In geology, a placer deposit or placer is an accumulation of valuable minerals formed by gravity separation during sedimentary processes. The name is from the Spanish word placer, meaning "alluvial sand". Placer mining is an important source of gold, and was the main technique used in the early...
s had been exhausted and the mother lode sought and discovered. Many such deep mines have been found in the mountains around Las Medulas. Mining would start with the building of aqueducts and tanks above the mineral veins, and a method called hushing
Hushing
Hushing is an ancient and historic mining method using a flood or torrent of water to reveal mineral veins. The method was applied in several ways, both in prospecting for ores, and for their exploitation. Mineral veins are often hidden below soil and sub-soil, which must be stripped away to...
used to expose the veins under the overburden.
The remains of such a system have been well studied at Dolaucothi in South Wales
South Wales
South Wales is an area of Wales bordered by England and the Bristol Channel to the east and south, and Mid Wales and West Wales to the north and west. The most densely populated region in the south-west of the United Kingdom, it is home to around 2.1 million people and includes the capital city of...
. Opencast methods would be pursued by fire-setting
Fire-setting
Fire-setting is a method of mining used since prehistoric times up to the Middle Ages. Fires were set against a rock face to heat the stone, which was then doused with water...
, which involved building fires against the rock and quenching with water. The weakened rock could then be attacked mechanically and the debris swept away by waves of water. Only when all opencast work was uneconomical would the vein be pursued by tunnelling and stoping
Stoping (mining method)
Stoping is the removal of the wanted ore from an underground mine leaving behind an open space known as a stope. Stoping is used when the country rock is sufficiently strong not to cave into the stope, although in most cases artificial support is also provided...
.
Pliny also stated that 20,000 Roman pounds of gold were extracted each year. The exploitation, involving 60,000 free workers, brought 5,000,000 Roman pounds (1,650,000 kg) in 250 years.
Cultural landscape
Parts of the acqueducts are still well preserved in precipitous locations, and including some rock-cut inscriptions.Research on Las Médulas had been mainly carried out by Claude Domergue (1990) . Systematic archaeological studies of the area, however, have been carried out since 1988 by the research group Social Structure and Territory-Landscape Archaeology of the Spanish Council for Scientific Research (CSIC
CSIC
The Spanish National Research Council is the largest public institution dedicated to research in Spain and the third largest in Europe...
). As a result, Las Médulas ceased to be only a gold mine with its techniques and became a cultural landscape
Cultural landscape
Cultural Landscapes have been defined by the World Heritage Committee as distinct geographical areas or properties uniquely "..represent[ing] the combined work of nature and of man.."....
in which all the implications of Roman mining were made apparent. The survey and excavations of pre-Roman and Roman settlements throughout the area allowed for new historical interpretations that greatly enriched the study of Roman mining..
A positive result of these systematic studies was the inclusion of Las Médulas as a World Heritage Site
World Heritage Site
A UNESCO World Heritage Site is a place that is listed by the UNESCO as of special cultural or physical significance...
in 1997. Since then, the management of the Cultural Park has been monitored by the Las Médulas Foundation, which includes local, regional, and national stakeholders, both public and private. Currently, Las Médulas serves as an example of good research-management-society applied to heritage
See also
- Dolaucothi
- Gold mine
- Gold rushGold rushA gold rush is a period of feverish migration of workers to an area that has had a dramatic discovery of gold. Major gold rushes took place in the 19th century in Australia, Brazil, Canada, South Africa, and the United States, while smaller gold rushes took place elsewhere.In the 19th and early...
- Hydraulic miningHydraulic miningHydraulic mining, or hydraulicking, is a form of mining that uses high-pressure jets of water to dislodge rock material or move sediment. In the placer mining of gold or tin, the resulting water-sediment slurry is directed through sluice boxes to remove the gold.-Precursor - ground...
- Naturalis HistoriaNaturalis HistoriaThe Natural History is an encyclopedia published circa AD 77–79 by Pliny the Elder. It is one of the largest single works to have survived from the Roman Empire to the modern day and purports to cover the entire field of ancient knowledge, based on the best authorities available to Pliny...
- Pliny the ElderPliny the ElderGaius Plinius Secundus , better known as Pliny the Elder, was a Roman author, naturalist, and natural philosopher, as well as naval and army commander of the early Roman Empire, and personal friend of the emperor Vespasian...
- Roman technologyRoman technologyRoman technology is the engineering practice which supported Roman civilization and made the expansion of Roman commerce and Roman military possible over nearly a thousand years....
- Roman aqueducts
External links
- Webpage of Fundación Las Médulas, with itineraries, virtual visit and practical information
- UNESCO official website
- Photo gallery and explanation of the explotaition system
- "Las Médulas, the Roman El Dorado". and Article by the Leonese writer Julio Llamazares.
- Spanish site dedicated to Roman technology, especially aqueducts and mines
- Social Structure and Territory-Landscape Archaeology research group