mines and mining

Greeks obtained gold and silver and ‘utility’ metals, copper, tin (for bronze), iron and lead, by mining and by trade; colonization extended their scope for both. Literary evidence for mining is mainly historical not technical. Epigraphical, archaeological, and scientific evidence has extended knowledge of industrial organization and techniques, and proved the early exploitation of certain ore‐fields. Climate, geography, and geology dictated methods: panning for gold (as in Asia Minor and Black Sea regions) was rarely practicable in Greece and its islands, while low rainfall reduced mine‐drainage problems and accounted for the elaborate catchment channels, cisterns and ore‐washeries designed to recycle water in the Laurium area. There the Athe‐nian lead‐silver mines were extensive (copper and iron ores were also exploited). In the same area, Thoricus has revealed sherd evidence for mining in late Mycenaean (see mycenaean age civilization) times. Sporadic mining continued in Laurium till the boom period of the 5th and 4th cents. bc. Opencast pits, oblique and vertical shafts (with cuttings for ladders, stagings, and windlasses), and underground galleries (some only 1 m. (39 in.) high) and chambers mark hillsides and valleys, along with extensive surface‐works (cisterns, washeries). In Macedonia and Thrace (Mt. Pangaeus) and on Thasos, gold and silver were mined. Control of the mainland mines yielded Philip II of Macedon an income of 1,000 talents annually. See slavery.

Roman

Imperial expansion gave Rome control over a wide variety of mineral resources. The Iberian peninsula (see spain), Gaul (Transalpine), Britain, the Danubian provinces (Dalmatia, Noricum, and Dacia), and Asia Minor became the major mining regions of the empire, and gold, silver, copper, lead, and tin the main metals extracted. Iron was found in many parts of the empire and, despite the presence of large‐scale iron‐mining districts in Noricum and the Kentish Weald, was usually exploited in smaller local units of production. Italy contained few precious metals, and Rome initially had to rely on imports from mines controlled by Hellenistic kings in the east and the Carthaginians in the west. After the defeat of Hannibal in 202 bc, Romans and Italians were soon exploiting the silver ‐mines in SE Spain around Carthago Nova. After the conquest of the Macedonian kingdom in 167, Rome regulated the operation of the Macedonian gold‐mines to suit its needs. The zenith of production at the major mines took place in the first two centuries ad. After the disruption of the 3rd cent., some mines were operating again in the 4th cent.

The Romans rarely opened up new areas of mining, but often expanded the scale of production and the variety of metals mined in regions already known for their mineral potential. Techniques of prospection relied heavily on observation of visible veins of mineralization in rock deposits and changes in soil colour. Of the precious metals only gold (and to a lesser degree copper) existed in a natural state. Silver, copper, lead, and tin occurred in compound metal deposits (ores) and required metallurgical processing to convert them into usable metals. Three main types of mining were practised: the exploitation of alluvial deposits; opencast mining of rock‐deposits found near the surface; and underground mining of deeper‐lying rock‐deposits. The Romans exploited alluvial deposits of gold and tin by panning or, if they were larger in scale, by flushing the alluvium with large quantities of water released at high speed in sluices to separate the metal‐bearing sands from the dross. In underground mines vertical shafts were sunk often in pairs occasionally to an impressive depth: 340 m. (1,115 ft.) at one mine near New Carthage. Horizontal galleries, often strengthened with wooden props, connected the shafts, increased ventilation, and allowed ore once mined to be removed from the ore‐face. Terracotta oil‐lamps were placed in niches to provide lighting. Drainage was a problem in deeper mines. Manual bailing was practised, but if possible, drainage adits were cut through sterile rock. In some mines chain‐pumps, Archimedean screw‐pumps, or a series of water‐lifting wheels were used. Mining tools, including picks, hammers, and gads, were mainly of iron, while ore was collected in buckets made of esparto grass before being hauled, in some cases by pulleys, to the surface.

Many mines (especially gold ‐and silver ‐mines) over time became the property of the Roman state, but cities and private individuals continued to own and operate mines. In state‐owned mines the state either organized production directly, as probably occurred in the gold‐mining region of NW Spain, or it leased out contracts to work the mines to individuals, small associations or the larger societates publicanorum (see publicani). Mineworkers were often slaves, but prisoners of war, convicts, and free‐born wage labourers also formed part of the workforce. Tombstones from mining settlements show that people often migrated long distances to work at mines. Soldiers were stationed at the larger mines, not just to supervise the labour force, but also to provide technological expertise. Any mining site needed a large number of ancillary workers to keep the labour force fed, clothed, and equipped, and to assist in processing ore into usable metals.