The lavrion mines

The Lavrion Mines Athanassios Katerinopoulos

Introduction Lavrion Municipality extends 15 km along the SE coast of Attica, about 50 km from the center of Athens (http://en.wikipedia.org/wiki/Laurium). Next to Lavrion there is cape Sounion and the well-known temple of Poseidon. Ore exploitation of the Lavrion area has a history of 5,000 years. The naval strength of Athens in the fifth century BC and the silver decorations of its buildings are indications of the riches of the Lavrion mines. Apart from the ancient silver mining, Lavrion is known worldwide for the variety and the beauty of its mineral samples. These can be still found underground in the galleries, but also on the surface, wherever mining waste has been left.

Kyanotrichite, Lavrion

A water tank in Soureza valley

A. Katerinopoulos (B) National and Kapodistrian University of Athens, Department of Geology and Geornvironment, Section of Mineralogy and Petrology, Panepistimiopolis, Gr-15784, Athens, Greece e-mail: akatern@geol.uoa.gr

N. Evelpidou et al. (eds.), Natural Heritage from East to West, C Springer-Verlag Berlin Heidelberg 2010 DOI 10.1007/978-3-642-01577-9_3,

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The Ancient Mines The great mining boom of Lavrion began in 483 BC, when the rich deposits of silver were discovered in Maronia (today’s Kamariza or Agios Konstantinos). The silver that at that period “flowed like water from the spring” came from the silver mines, the famous arghyreia, from which the state and businessmen made astronomical profits in the fifth century. It is reported that a certain Kallias earned 1,200,000 drachmas (5.5 tons of silver) in 1 year (Marinos and Petrascheck, 1956).

The ancient underground galleries extend over a total length of hundreds of kilometres and were built on six levels. More than 1,000 shafts have been found in the region, some of which are as deep as 119 m. In the wider Lavrion area one can still see hundreds of gallery entrances and shafts, especially in the Plaka and Kanariza areas (Konofagos, 1980).

The galleries were hewn out using nothing but pickaxes, hammers and chisels.

Fire was used to a lesser degree where explosives would be utilised today. That is, the rock would be heated, and then water was thrown on it suddenly, causing the rock to shatter owing to the abrupt contraction. It is calculated that the work of building a gallery proceeded at a rate of 12 m a month, while for shafts the rate was just 5 m a month.

The area of Lavrion is extremely arid. The lack of the water led to the construction of a drainage system bringing the water into huge tanks. Just before the main tank there was a smaller one for the precipitation of any impurity. One should point out the perfect impermeability of these tanks. Note that the same insulation material, used 2,500 years ago in Lavrion waterproof tanks, is also used nowadays all over the world for the insulation of radioactive waste storage pits. Water tanks and the remaining of the drainage system can be still seen in the Soureza valley.

Using Lavrion silver, Themistocles was able to build the powerful Athenian fleet, which together with that of the rest of Greece saved the ancient civilisation at the battle of Salamis. The Athenian triremes then numbered 200, out of a total of 314 in Greece. Every trireme cost two talents, which were equivalent to 54 kg of silver.

Before the Peloponnesian war, 270 tons of silver were stored in the treasury of the Parthenon and as much again was in circulation as coinage: the Athenian silver coin “glafka” (=owl). The same owl appears on the front face of the Greek 1 Euro coin.

The glafka coin

Remaining of the ancient drainage system

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During antiquity, the mines belonged exclusively to the Athens city-state, which granted concessions to exploit them primarily to Athenian private citizens. The concessionaire would hand over one twentieth of his profits to the state. At the period of maximum activity, this amounted to 50–100 talents a year (1 talent = 27 kg silver or 6,000 silver drachma).

State control of the operation of the mines and of their production was systematic and strict. For this reason there was special mining law and a special court to enforce it. Anyone would be punished who exceeded the limits of his concession, operated the mine that had been ceded to him in an irregular way, or jeopardised the future of other mines. It is reported that under Lycurgus (330 BC), a certain Diphilos, known for the large profits he extracted from Lavrion, was put to death for his greed, because he cut down the mineral columns that were left intact to prop up the galleries.

The Slaves Looking at the Athenian frescos one can see figures of miserable slaves working in the Lavrion mines. These poor creatures were considered “speaking tools” and common merchandise, without any political or legal rights.

Nevertheless there were unwritten laws according which any slave, if treated cruelly, had the right to take shelter in a temple; his master was then obliged to sell him.

No master could put his slave to death without a court judgment. Also any Athenian free citizen could accuse any person of treating his slaves cruelly. In the fifth century BC the slaves in the Lavrion mines numbered about 15,000.

During the work there were guards at the entrances of the galleries and on the top of towers, to prevent the slaves from escaping. But there was a special respect for their religious customs, and even burial traditions.

Despite these conditions, there was a number of slave revolts, the most important being the one in 413 BC (during the war between Athens and Sparta) resulting in the defeat of Athenians, due to the poor state of the economy.

Lavrion then became inactive, so Pausanias (second century AD.) said “Near Sounion, at Lavrion, Athenians’ silver mines existed”. This continued for centuries, till 1860.

The Ore The ancient Athenians developed a very advanced technique to enrich the ore. After the hand-picking, the material was crushed in rock mortars and brought to special “lavatories”, where they separated the argentiferous galena from sphalerite, pyrite, calcite and the clay minerals. A restored lavatory can be seen at Thorikos, next to the ancient theater, one of the oldest in Greece. A characteristic of this theater is the

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elliptical pattern, in contrast to the semicircular pattern of later ones. There is also the oldest gallery found in Lavreotiki (3,000 BC).

Restored lavatory at Thorikos

The ancient theatre at Thorikos

Dozens of lavatories are preserved at Soureza valley, an archaeological site, about 2 km from Ag. Konstandinos, well worth a visit.

On the way to Soureza, next to the park, there is a spectacular depressed area, named “The chaos”, formed by the collapse of a huge cave (http://www.mylavrio.gr).

One of the ancient lavatories in Soureza valley

The chaos

The enriched ore was transported to the furnaces in order to separate the Ag-Pb alloy. Successive layers of ore and charcoal were layered and put in fire, so as the heavier argentiferous lead was concentrated at the bottom while the lighter “slag” flowed from the top. The slag was discarded as a metallurgical waste. Huge piles of slag covered the Lavreotiki area. Today only a few remaining samples can be found, as the material was reworked in order to exploit the remaining silver content.

The separation of the Ag-Pb alloy into lead and silver fractions (cupellation) was done in special furnaces by an extremely difficult and precise procedure. The alloy was melted by the burning of wood with the help of hand-bellows. This procedure is still used in silver metallurgy.

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Experienced workers melted the alloy at 950◦ C, when the lead oxidized to PbO flowing into a ceramic bowl, while the purified silver (not affected by atmospheric oxygen in this temperature) remained in the furnace. The procedure was considered completed when there were “flowers” i.e. bubbles of the atmospheric air appearing as white flowers on the silver surface. This silver was 98% pure and ready for coinage. From 1,000 kg of silver-lead ore they could get 200 kg of lead and 25 kg of silver. The lead was used at first to connect parts of columns, and to stabilise statues.

Later it was used for drainage pipes.

The income from the Lavrion mines maintained the economic strength of the city of Athens until the rule of Alexander the Great. By the end of the second century BC, during the roman expansion, the mines were closed.

Modern Lavrion History In 1860 the Greek mining engineer Kordelas visited Lavrion and wrote a memo to the Greek Ministry of Development, referring to the possibilities of reworking the ancient slag (Kordellas, 1993).

At the same time the Italian businessmen J. B. Serpieri recognized the ballast of a ship thrown at the Italian coast as pure smithsonite. Asking for more information he learned that the ship was returning from Lavrion-Greece, where it was loaded by this “useless” ballast.

Serpieri visited the Lavrion area and, bearing in mind the Kordelas report, he established, along with the French businessmen Ilarion Roux, the Italian-French company «Ilarion Roux et Cie» (1864). The company started exploiting some new deposits but mainly reworking the ancient slag.

It was the largest company in Greece at that time employing 1,200 workers, operating 18 Spanish furnaces of the “castilliano” type, a large turnery and their own locomotive.

But the company only had permission to exploit new ore deposits and not the ancient slag that was “a product of the human activity” and in 1869 legal proceeding were started by the Greek state. The negotiations ended 4 years later when A. Sygros bought the company and renamed it “Greek metallurgy of Lavrion”. At the same time Serpieri established a new company: “Compagnie Francaise des Mines du Laurium” The small settlement of Lavrion expanded to a city of 10,000 people. The two companies owned the houses and the shops. They also were taking care of the schools and the churches of the town, as well as pharmacies and the hospital treatment of the workers.

The Greek company was the first one in Greece that used electricity, telephone and other modern technologies. They also constructed the railway that connected Athens with Lavrion (1882–1885). The company lasted until 1917, when the slag deposits were exhausted (http://www.eranet.gr/lavrio).

The French company lasted until 1983, when it was sold to a British company that did not continue the mining.

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The Lavrion Minerals The broader mining region of Lavreotiki constitutes a natural museum, since in it can be found more than 15% of all the recognised minerals on earth, known world-wide for their variety and for their particular beauty (Katerinopoulos and Zissimopoulou, 1884).

The Athens University Museum of Minerals and Rock owns a very large collection of Lavrion minerals. All the samples are outstanding, but the pride of the collection is a unique stalactite made of smithsonite, about 70 cm long.

Part of the Lavrion minerals collection, Museum of Mineralogy-Petrology, Athens University

The stalactite of smithsonite. (Museum of Mineralogy-Petrology, Athens University)

The Slag Minerals Despite the highly developed metallurgical techniques taking place in the ancient factories, the ancient Greeks could not take out all the silver from the ore and, after smelting, they discarded the slag, sometimes into the sea.

The sea water contains Na, Cl and other trace elements, which penetrated for 1,000 years into the slag. The chemical reaction with lead, silver and other trace elements existing in the slag resulted in the growth of perfect crystals of various minerals, some of which are very rare and exist only in Lavrion, such as Thorikosite (named from the locality Thorikos).

In winter the slag is carried out of the sea by waves and then lies scattered throughout the coast of Lavrion. Collectors come from all over the world to collect it.

Whenever you visit Greece do not miss out Lavrion – a place of history and beauty.

References Marinos, G. & Petrascheck, W.A. 1956. Lavrio IGSR (ed.) Athens, McDonald, 248 p.

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Katerinopoulos, A. & Zissimopoulou, E. 1884. The minerals of the Lavrion mines. Gr. Assoc. Min. Fossil Collectors. Athens: 304.

Konofagos, K. 1980. Ancient Lavrion and the Greek technique of silver production. Ekdotiki Ellados.

Kordellas, A. 1993. Lavrion (translation of “Le Laurium, Marseille, 1869”), Library of the society of studies of Lavreotiki No 6. http://en.wikipedia.org/wiki/Laurium http://www.eranet.gr/lavrio/html/glavrio.html http://www.mylavrio.gr/index.php?option=com_content&taskviewid=41&Itemid=50