In such a geologically active area, it is not surprising that ores containing metals including gold, silver, copper, lead, and iron were often found. There were coal seams, too, but they were little used in ancient times. The Greeks looked down on mining as degrading labor, and they were undoubtedly right; the life expectancy of the slaves who labored in the mines was regrettably short. The Athenians struck their famous coins, the drachmas bearing the image of an owl, from silver mined at Laureion. Silver mines on the island of Thasos had been worked by the Phoenicians before the Greeks. The Iron Age began about 1000 bce, sparking a search for exploitable ores of that metal. The Spartans had an iron mine in southern Lakonia on Mount Taygetos, the source of steel that they manufactured into weapons, and from which they made the cumbersome Spartan iron money called obols (‘‘spits’’). Philip of Macedon conquered Mount Pangaion in order to exploit the placer gold there, thus gaining the riches he needed to hire spies and to bribe corrupt officials. Greek miners accomplished work on an amazing scale considering the level of their technology. Many mines were of considerable size even by modern standards. At Laureion, more than 2,000 vertical shafts gave access to over 140 km of tunnels. The methods used for extraction of the ores were washing them from the surrounding material by placer and hydraulic mining, open-pit mining, and tunneling into veins deep below the earth. A never-ending problem in mines was drainage, which along with the need for air supply limited the depth to which shafts and tunnels could be sunk. Where topography permitted, miners could dig tunnels as drains. Elsewhere, water was raised by bailing, or by means such as the Archimedean screw pump. Drainage from mines polluted water with many substances, some poisonous.
Quarrying presented many problems similar to those encountered in mining. Since large, potentially useful blocks of various kinds of stone had to be cut and removed, most quarries were of the open-pit type, but sometimes tunnels and galleries were excavated underground. A great weight and volume of substance removed from the earth was required for the production of concrete and mortar. Mortar was known as early as the Bronze Age in Greece.
Mining and quarrying had pervasive impacts on the ancient landscape. Herodotos (6.46-7) said that a whole mountain on the island of Thasos had been turned upside down by gold miners. Counting it together with other mines on the mainland at Skapte Hyle on the western flank of Mount Pangaion, where a forest was removed by the excavation and by felling for fuel and timber, the Thasians realized an annual profit of200-300 talents. Wertime (1983: 448) says the mines at Laureion inflicted ‘‘a great scar upon the Attic landscape,’’ and ‘‘by the time of Strabon the wooded surface of the region had been completely bared to provide timber for the mines and charcoal for the smelting of the ore.’’ The ancient quarries of Mount Pentelikon are still visible. Mining also diverted enormous quantities of water, much of it near the headwaters in the mountains, which deprived farmers lower down of much of the supply and polluted what was left. Air quality was another concern in mines. Contamination came from gases trapped underground, and from the fumes of fires used for lighting the tunnels and for breaking rocks. Conditions in the workplace environment were appalling.
Metallurgical industries processed ores to recover the useful metals. They used furnaces that were often provided with chimneys. Other smelters were excavated as pits in the ground. Smelting required large amounts of fuel to reach the desired high temperatures. Metalsmithing required more fuel and produced additional pollution. Minting of coins generated demand for precious metals. Each ton of silver required removing about 100,000 t of rock from the mines.
Pottery was one of the most prolific industries of ancient times. Ceramic factories required prodigious quantities of fuel to heat the kilns. Brush and vine cuttings burned hot but fast, and fuel-wood from logs was used as well (Cato De Agricultura 38.4). Kilning of limestone for plaster and mortar got its material from quarries, but in times of war and social upheaval might also use fragments of buildings and statues. To supply one limekiln for one burn in the Greek mountains required a thousand donkey-loads of juniper wood, and fifty kilns required annually 6,000 t of wood (Wertime 1983: 452).
Along with household use in cooking and heating, industry produced a demand for fuel-wood and charcoal that contributed to deforestation. To smelt one ton of silver, however, required 10,000 t of wood. The centers of mining and smelting became the areas most depleted of forests; copper mining in Cyprus was especially destructive. In the latter area, now devoid of trees, archaeologists have found huge deposits of wood ashes (Thirgood 1981: 57). Air pollution came not just from wood and charcoal smoke, but also from the fumes of hazardous substances such as lead and mercury produced during metallurgical processes.
World History
