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Sylvia Rose

Almadén Mines: Ancient Mercury Extraction

The Almadén Mines in central Spain have an infamous past driven by profit and greed. The deadly history of ancient Almadén revolves around mercury, cinnabar, the waking nightmare of hardships endured by those condemned to the horrors of poisonous death.



look way up ... a hole

The name Almadén is from the Arabic: المعدن, romanized: al-maʻdin, lit. 'the metal', 'the mineral' or 'lode', and so by extension, the place where these are excavated, 'the mine'. The Almadén region is the world's most important mercury mining district until it's closed in 2002.


The complex is made up of the huge Almadén and five more mines of less importance. Within this area the presence of cinnabar (HgS, the main mercury ore) has been described at up to 60 sites.



Cinnabar (HgS)
Cinnabar (HgS)

History


Cinnabar has been mined in Almadén for over two millennia. The history of Almadén involves the evolution of economic and social concern. The mines provide valuable resources but also horror, sickness and death. The area is conquered by Romans c. 133 BCE.


The Romans start extracting cinnabar from Almadén after vermilion is commercialized in the Mediterranean. Pliny the Elder (23-79 AD) describes distillation of native mercury from cinnabar in marmites, or giants' pots, huge holes carved into stone by glacial action.



A marmite (round hole) in rock
A marmite (round hole) - they can be deep, forming natural cauldrons.

Due in part to Roman roads, the region grows to an important point in commerce. Cheap labor, processing efficiency and ever-expanding trade routes contribute to its success. The Almadén mine complexes become the largest source of mercury in the world.


Substantial quantities of mercury and cinnabar travel through Europe and the Americas, shipped in lead containers. Lead and glass are among the few materials mercury doesn't consume. From there the mercury may be poured into smaller receptacles for sale or trade.



In 474 AD, the Visigoths expel the Romans. The Moors drive out the Visigoths in 711 AD and create a great civilization. In a tumultuous time of “Reconquista" through years 801 - 1492, Christians make gradual conquests, and in 1151 capture Almadén under King Alfonso VII.


The economic impact of the Almadén mines on Spain is immense. Wealth generated from mercury exports boosts the Spanish economy, especially during the colonial period when mercury is crucial for the extraction of silver and gold in the Americas.



Mercury Quicksilver & Beading Behavior
Mercury Quicksilver & Beading Behavior

Mercury


The mining process is labor-intensive and traumatic. Miners face health hazards daily, as exposure to mercury fumes cause severe neurological and respiratory damage. 


Cinnabar (HgS) is a compound of mercury (Hg) and sulfur (S). Always practical, the Romans use mercury in paint. Paint containing mercury is found in Roman homes buried by the volcanic ash of Mount Vesuvius' famous eruption in 79 AD. The pigment vermillion is popular.



vermilion in Pompeii
Vermilion in Wall Painting, Pompeii

Romans also use mercury in a technique of gold-plating. Gold and mercury are melted together, and the mixture brushed onto the substrate. Heat is applied to evaporate the mercury and send invisible toxic fumes throughout the work area.


Termed hydrargyros  during the time of Aristotle (384-322 BCE), the liquid metal is later called Argenturn Vivurn “alive silver” or in English “quicksilver". The name mercury comes from the association of the metal with the planet Mercury by 7th century AD alchemists.



Mercury metal, sign and planet
Mercury metal, sign and planet - lead flasks used for shipping Hg would be marked with the mercury sign

Ancient and medieval astrology link specific metals with planets. The geocentric planetary schema of Greek astronomy coincides with a pattern of ranking of the corresponding metals by atomic number, even though awareness of the atomic properties is not yet fully known.


Vermilion


Another cinnabar product from Almadén is vermilion, a deep scarlet red artists' pigment. Cinnabar is ground to powder to produce the only bright red available to ancient painters and dyers. Vermilion is also used in cosmetics to bring a blush to the skin and lips.



In Mesoamerican societies it's used to powder paint the dead. An ancient synthetic process to create cinnabar (HgS):


"Black mercury sulfide is created by mashing mercury and melted sulfur together, followed by heating the mixture in a retort. This process results in vapors condensing into bright red mercury sulfide."

Synthetic vermilion is made by either a dry or a wet method. The dry method is thought to be invented in China by the fourth century BCE. It consists of heating mercury and sulfur in a sealed container. Vermilion or red lacquer is prized in Chinese artworks.



Chinese Red Lacquer Plate
Chinese Red Lacquer Plate

Mercury Madness (Mercury Poisoning)


It begins with tremors and memory loss and progresses to confusion, seizures, insanity and death. Miners witness the advanced effects on others, and know their fates.


Despite the risks, demand for mercury increases operations at the mines. Miners and processors are convicts and low-quality slaves. If lucky, a convicts could be released before the full extent of mercury poisoning sets in.



pain and suffering

About 25% of cinnabar miners die while countless more get sick, from tremors to seizures and madness. Comparatively, almost 100% of mercury processors die. Mining and processing are done at the same complex.


Separating mercury from its sulfur compound involves industrial scale distillation. Even at room temperature mercury evaporates, and heated it evaporates faster. According a medieval writer work at the mines is fast and frenetic.



Cinnabar distillation apparatus, medieval German
Cinnabar distillation apparatus, medieval German

Workers handle cinnabar and inhale invisible toxic fumes constantly. The slaves doomed to the mines are branded as rebellious or undesirable thus can be bought for a fraction of the price of slaves suitable for society. They're used up and replaced by others.


Mercury silently seeps into the lungs and bloodstreams of those who work the mines. As the extraction continues, the name Almadén is a somber reminder of the sacrifices made in the name of someone else's wealth and power.



ancient civilization colosseum


Complaints about the conditions of the mining complex prompt an investigation in the 15th century. Dwellings are overcrowded, poorly constructed, and lack basic sanitation. Access to clean water is limited. According to the complaints, cave-ins and mine fires are commonplace.


The investigators come to take a look. They conclude there's plenty of room in the housing constructions, miners are well fed and all precautions are taken for their safety.



a feast with vintage flair

During the 15th and 16th century, the Fugger family, German mercantile and banking dynasty dominates European business. The Fuggers of Augsburg, two German bankers, administer the mines in the 16th and 17th centuries in return for loans to Spain.


The Romans use convicts in mines under the punishment damnatio ad metalla, which condemns slaves and criminals to work in mines. Around the 18th century the Fuggers are still using convict labor, as a cheap alternative to freed workers, who complain too much.



Crystal Cinnabar (HgS)
Crystal Cinnabar

Slavery is outlawed by Spain in the 19th century. Even before then, many free workers are drawn into a cycle of poverty effectively binding them to the mines out of economic need. Due to health hazards, in 2002 it becomes illegal to mine mercury in Spain, and the mines close.


The site is now a museum.



Non-Fiction Books:


Fiction Books:

READ: Lora Ley Adventures - Germanic Mythology Fiction Series

READ: Reiker For Hire - Victorian Detective Murder Mysteries












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